[BETA POST to get the content out there, will brush up if there's interest]
TL;DR: In 2019, still can't go wrong with the Wilson US Open Extra Duty or Slazenger Wimbledon. You know how to shop...
Since a friend asked me about this the other day, here are some quick thoughts on the state of tennis balls in 2019. There surely are a lot of options on the market - but subjectively, tennis balls seemed to have been getting worse for some time...
Mainly, I'm thinking this because of my fond memories playing with the original Dunlop Tournament ball in Germany, e.g. back in the 90s. It felt and still feels like the only "normal" ball you needed. It played great and lasted pretty long. Size, weight, felt, and pressure felt just right.
Overall it had a very solid but still comfortable feel to it. It took on spin (i.e. it would land in the court when it should), you could hit winners with it, and after a short break in during warmup in wouldn't degrade much over the course of a long match. In other words, it wasn't limiting your play and experience.
In comparison, apart from different feel, I thought some other recent kinds of balls would consistently fly long. And these days, you often need to pop open a new can for the 3rd set! In some tournaments that's even mandatory... Other balls are so hard, it literally hurts.
As for the Dunlop Tournament, it was just unfortunate that it was so expensive. In your local sports shop it would cost the equivalent of up to $5 / 5€... per ball! When assessed in "cost per enjoyable contact" the ball would get a bit more price-competitive, but still you really had to think hard about when and how many to purchase. One of the successors, the Dunlop Fort Tournament, has gotten a tad cheaper for all the common reasons (e.g. online, competition), but it's still expensive.
It's worth a quick mention that there are also some regional (continental?) differences. While balls in Europe seemed to have been built to last, most balls in the US would be OK for one hit. Pricing was set accordingly - 1 ball in Europe = 1 can of 3 in the US. (So when your US court time is expensive, don't show up with just 3 balls!)
So now, how to pick a ball in 2019? First, thinking of the main use cases, I guess those would be match practice, live-ball practice, dead-ball practice (with partner / coach or ball machine. The more hits, the more wear of course, with a ball machine adding a multiplier there. Ideally there'd be one ball for everything, same or similar to the ones you'll be handed at competitions.
Especially for practice, the more balls the better. Well - at around 200 it might get a bit crowded on court... But still, apart from being enjoyable to hit, they'd need to be somewhat affordable and lasting. Even though I'm still reminiscent of the Dunlops, the better ones are still twice as expensive as pretty good alternatives.
In the US, my favorite ball after trying most used to be the Pro Penn ATP Extra Duty. Another 5.0 tennis friend used to describe them as "friendly", which stuck with me as fitting. You could have a great hit and still put them in a basket for a few more practice sessions. Currently it's not clear to me if they have an official successor after losing the ATP sponsorship to Dunlop. Haven't done much research here since the following 2 meet my current needs:
I've also always liked the Wilson US Open Extra Duty. They're not as light and shaven as some of the other hard court balls. While they can be a bit rocky for the first ~100 contacts, they become enjoyable and stay that way for a comparably long long time. PBI for example uses that one as worldwide practice ball, even on clay, which inspired me to follow suit. I tried them for ball machine use as well, and they seem to manage that much better than the mix of other balls in there. Even though they're officially designed for hard court, they've worked well for me not only on clay, but also on carpet. Guess for cross-surface compatibility it mostly comes down to having enough friction, so that the ball doesn't slide as much on bounce...
In addition I've been enjoying the Slazenger Wimbledon, which is a similar-playing half-priced alternative to the good Dunlops. For ~3 sets they hold up pretty well. Then they turn a bit slow-playing but maintain their size and felt, so generally still good and comfortable for practice. At times these characteristics could actually be exactly what you want - for example for practicing longer rallies at the beginning of the clay season. Or making things more comfortable for beginners. I've also found the Slazengers very if not most enjoyable on hard court - which goes counter the Wimbledon branding's association with grass.
Other balls I had recently tried after shortlisting were
Bottom line, the above-mentioned Wilson and Slazenger balls seem like good all-around options. If money is less of a consideration, you could also try the high-priced Dunlops or the second-grade Dunlop Trainers (1 out of 4 tends to go flat pretty quickly).
TL;DR: In 2019, still can't go wrong with the Wilson US Open Extra Duty or Slazenger Wimbledon. You know how to shop...
Since a friend asked me about this the other day, here are some quick thoughts on the state of tennis balls in 2019. There surely are a lot of options on the market - but subjectively, tennis balls seemed to have been getting worse for some time...
Mainly, I'm thinking this because of my fond memories playing with the original Dunlop Tournament ball in Germany, e.g. back in the 90s. It felt and still feels like the only "normal" ball you needed. It played great and lasted pretty long. Size, weight, felt, and pressure felt just right.
Overall it had a very solid but still comfortable feel to it. It took on spin (i.e. it would land in the court when it should), you could hit winners with it, and after a short break in during warmup in wouldn't degrade much over the course of a long match. In other words, it wasn't limiting your play and experience.
In comparison, apart from different feel, I thought some other recent kinds of balls would consistently fly long. And these days, you often need to pop open a new can for the 3rd set! In some tournaments that's even mandatory... Other balls are so hard, it literally hurts.
As for the Dunlop Tournament, it was just unfortunate that it was so expensive. In your local sports shop it would cost the equivalent of up to $5 / 5€... per ball! When assessed in "cost per enjoyable contact" the ball would get a bit more price-competitive, but still you really had to think hard about when and how many to purchase. One of the successors, the Dunlop Fort Tournament, has gotten a tad cheaper for all the common reasons (e.g. online, competition), but it's still expensive.
It's worth a quick mention that there are also some regional (continental?) differences. While balls in Europe seemed to have been built to last, most balls in the US would be OK for one hit. Pricing was set accordingly - 1 ball in Europe = 1 can of 3 in the US. (So when your US court time is expensive, don't show up with just 3 balls!)
So now, how to pick a ball in 2019? First, thinking of the main use cases, I guess those would be match practice, live-ball practice, dead-ball practice (with partner / coach or ball machine. The more hits, the more wear of course, with a ball machine adding a multiplier there. Ideally there'd be one ball for everything, same or similar to the ones you'll be handed at competitions.
Especially for practice, the more balls the better. Well - at around 200 it might get a bit crowded on court... But still, apart from being enjoyable to hit, they'd need to be somewhat affordable and lasting. Even though I'm still reminiscent of the Dunlops, the better ones are still twice as expensive as pretty good alternatives.
In the US, my favorite ball after trying most used to be the Pro Penn ATP Extra Duty. Another 5.0 tennis friend used to describe them as "friendly", which stuck with me as fitting. You could have a great hit and still put them in a basket for a few more practice sessions. Currently it's not clear to me if they have an official successor after losing the ATP sponsorship to Dunlop. Haven't done much research here since the following 2 meet my current needs:
I've also always liked the Wilson US Open Extra Duty. They're not as light and shaven as some of the other hard court balls. While they can be a bit rocky for the first ~100 contacts, they become enjoyable and stay that way for a comparably long long time. PBI for example uses that one as worldwide practice ball, even on clay, which inspired me to follow suit. I tried them for ball machine use as well, and they seem to manage that much better than the mix of other balls in there. Even though they're officially designed for hard court, they've worked well for me not only on clay, but also on carpet. Guess for cross-surface compatibility it mostly comes down to having enough friction, so that the ball doesn't slide as much on bounce...
In addition I've been enjoying the Slazenger Wimbledon, which is a similar-playing half-priced alternative to the good Dunlops. For ~3 sets they hold up pretty well. Then they turn a bit slow-playing but maintain their size and felt, so generally still good and comfortable for practice. At times these characteristics could actually be exactly what you want - for example for practicing longer rallies at the beginning of the clay season. Or making things more comfortable for beginners. I've also found the Slazengers very if not most enjoyable on hard court - which goes counter the Wimbledon branding's association with grass.
Other balls I had recently tried after shortlisting were
- 2019 Dunlop ATP balls - seemed a bit too soft, at least in Europe.
- Balls Unlimited Black Code - liked them for a while too - initially somewhat comparable to the Slazenger, however they went flat pretty quick.
- Head Championship - hard as stone at first, then become OK for X months / hours, then suddenly die. They smell really bad, so don't leave them in your car or in a room where you spend a lot of time.
- Tennis-Point branded Premium - felt a little harsh and are not really playable after their first use
Bottom line, the above-mentioned Wilson and Slazenger balls seem like good all-around options. If money is less of a consideration, you could also try the high-priced Dunlops or the second-grade Dunlop Trainers (1 out of 4 tends to go flat pretty quickly).
Finally, if you're about to play competitively, don't forget to pick up the kind they'll be using there for at least one hit before your first match!