Not going to write a full-blown review here, but just make some observations with my time so far with the rubber, after spending nearly a year with Roxon 450.
Spin
I played a handicap round robin for the club's B grade opening night tonight and so was the first time using the rubber on my Bty Gergely against my usual playing peers. The rubber is not as grippy as the Roxon, but still better than many other tensors I've tried. Serving is a little harder work, but can still produce decent spin to catch an unwary opponent out. Looping is also not as easy, but I have adjusted to its throw, which when I first ever hit with it had me dumping slow loops into the net. I feel that the adjustment has compromised how much wrist can be thrown into the ball to get the loop spin, so the loops are not as venomous.
Speed
The rubber has plenty of speed. Its where it shines most. I think it probably has more lower gears than the Roxon just slightly as the catapult feel is not as pronounced, probably due to the harder sponge. I haven't noticed that its greatly faster than the Roxon though. In fact, the Roxon may still have the edge given its greater catapulting effect. The Proton is certainly fast enough to put a smash away. Not sure I feel quite as "sure-footed" in smashing with it as Roxon as its not quite as forgiving. Having said that, it responds well to the right shot.
Blocking
While the rubber blocks fairly well, I miss the ease of blocking with the Roxon. I don't think I get the same blocking control with the Proton and it doesn't inspire as much confidence of blocks going on. Its not terrible at it, I think I have just been spoilt by the Roxon for this as it does it so gracefully and close to effortlessly.
Chopping
I think Proton is superior to Roxon in this department. I don't chop a lot off the FH, but when I have, Proton produces a lower sharper shot.
Overall
I'm giving the Proton some time because I don't want to waste the money I spent on it and its not an altogether bad rubber. I feel that if I can get used to playing with this and do well with it, going back to the Roxon will be a step up again. A bit of a reality check if you like. Overall though, I feel the Roxon is a better rubber for a player at my level* and suits the Gergely blade better.
* I'm sure most reading this post will know I was playing division 2 of B grade at Dandenong, one of Australia's biggest clubs. Having won the premiership last season, I head into the new season in 1st division of B grade.