I've got two. One has a broken trigger and the both of them are so fucking big that I have to set them on my lap to use 'em like a joystick.
Ok...maybe not that big.
I'm not really a fan. If you like the Duke, the size is about the same on the MadCatz I have. Maybe it's even bigger than the Duke? The face buttons are reasonable. The triggers are pretty lame. They have a strange feel to them and lack enough travel. The left analog is ok. The right one doesn't seem as good for some reason even though it's a similar stick. The crosspad is big and when it's worn it feels like mud.
The S-Controller is better IMO. But really, I have to try out a bunch of Xbox controllers because neither the MadCatz or the S is completely satisfying to me and the Duke is just too damn big.