I've been searching around for one of these since release, and haven't been able to find one. I'm so glad that I put in the effort and got one for myself, because it's really night and day with Street Fighter 4. It does have a bit of a learning curve, especially if you are used to using the Xbox Controller, but I have to say pulling off some of those challenge mode trials were near impossible without this.
I spent several hours trying to get some of the hard and even the later normal challenges done on the controller with no luck. Within about 10 minutes of using the controller I had already passed maybe half of the challenges I wasn't even close to completing before.
The button response is awesome, it's so crisp. My only gripe is I'm not a fan of the ball top joysticks, I like the bat, but that's just personal preference. Another thing, is the ball on top rotates rather loosely, so sometimes you think your joystick is somewhere it's not. However, I consider all that a part of getting used to something new, (and 100 times better). I haven't tried the fightpad, or the standard fightstick yet, but I can honestly say, that this is one controller I wouldn't miss if you really want to be able to fully enjoy Street Fighter 4.
Sizewise? It's huge, and it does NOT move at all. I was really jammin on the controller, and it didn't move from it's spot on the table once. It has a nice weight to it, not too heavy, but it doesn't feel like a tiny paperweight. The art is really nice, the buttons and joystick are top notch quality, (suprising considering its from Mad Catz), and the turbo function is really easy to program. I'm also more of a fan of the concave buttons, not the convex. (I like them to dip in, not bow out), but these have a really great feel. I understand these are top quality parts, but I can't help but feel like after pushing the jab button enough times it's going to stop working so well, so at some point down the road I'm going to get some nice(er) buttons, with the battop joystick.
I was a bit torn between this and the HRAP, and one of the things this has, that I don't believe the Hori has, is the fact you can switch between modes for the joystick. Whether you want it to act like the Left Stick, Right Stick or Dpad, that means you can use it for well... any game you want, without worry that it's not going to be compatible because you aren't controller the right directional pad.
Overall though 5/5, totally worth the money. Get it, got it, good.