Okay, that's it then I guess, I'll be going for the 360 controller. Can't possibly be worse than the dual action. It comes with the best compatibility these days, has a 3 metre cable, which is nice, and has the console-style build quality (that's supposed to be good, right?).
The D-pad being a weak part is slightly worrying, but I suppose I could take that risk. Can't possibly be worse than the P2500 I think. After it broke I could actually see how brittle it was: a huge pad connected on a small stick in the centre. Even if the D-Pad is only a bit smaller, it'll already be a lot better, for both durability and control.
Placement is ok for me - I'll be using the thing for more things than just SF4, like GRID, and having the joystick up there is useful in those situations :)
edit: order placed. Should be here tomorrow :)
Ugh, sorry to tell you but a 360 controller is pretty trash for SF4. I have SF4 for the 360 and I pretty much bought a PS2 controller just so I could play SF4 (I already had a PS2->360 adapter from before).
Well I guess you could use the analog sticks. But the d-pad is terrible. Be prepared to re-learn how to execute combos.