Ok, I just read through this thread.
I recently switched from Hurricane commercial orange sponge to Hurricane provincial blue sponge. It took me some time to get adjusted to the blue sponge. After all at the same degree of hardness (39) for both orange sponge and blue sponge, the blue sponge is just harder. Less bouncy.
My blue sponge did NOT curl up as much as the orange sponge during the boosting process. I would say that after a couple heavy, generous layers of booster, the orange sponge is more lively and more bouncy (more ESN rubber like) than blue sponge!
But when I am used to the blue sponge and when I start hitting harder, the top end speed of the blue sponge shows up and I don't think I can go back to the commercial orange sponge anymore. Now the bouncy, well boosted commercial orange sponge feels "uncontrollable" at times for me.
Also recently, due to the expense of Hurricane provincial blue sponge (which costs about $49-55 per sheet depending on where I source it), I pulled out a brand new sheet of Sanwei Target National lying around in my stock and put it on a blade. I actually really enjoy playing the STN! STN plays just fine. Tacky top sheet like the old hurricane I was used to. The sponge is hard, like Hurricane provincial blue sponge. I don't think the STN sponge is as lively as even Hurricane blue sponge but I can play with it. Both Hurricane and STN have low throw angles which makes it going back and forth between those two rubbers very easy for me. I love love low throw angles on my forehand.
So the side story is, recently I switched to short pips on the backhand so I set up Hurricane provincial blue sponge on a couple of those blades. Due to how long it takes for my source (Aliexpress) to get me those rubber, at a pinch, one of my regular blades' forehand rubber went dead. So I slapped on STN there. The BH of that blade is Rozena.
Then I realized with my short pips blades, I play very well against players who have inverted on both sides. But when I play against pips player, my backhand is rendered useless and I keep on hitting the ball into the net on that side. It confuses the hell out of me because I know how to play against pips! Therefore, I had to take out my double inverted blade (STN on the FH and Rozena on the BH) and start spinning the ball all the time. And I have had quite a bit of success in doing so playing against pips players.
Therefore within each training session at the club, I have no problem going back and forth between the two sets of blades, depending on what my opponent has!
In conclusion, it really depends on how you play. For $25-$30 a sheet for STN, I find it to be good enough to replace my $48-$55 a sheet of Hurricane provincial blue sponge. I like STN.
But some people here on this thread do not like STN at all. And by the way, I hate Rxton series and Big Dipper, etc. Sorry, everyone plays a bit differently.
That is why take all the reviews on the site with a grain of salt. And that's also why I have been posting less and less. I know what I like. I know what my hands like. I don't really read that much equipment review anymore.
