About a year ago I bought four different gamepads to use with emulated games: Gravis GamePad Pro, Gravis Eliminator GamePad Pro, Logitech Dual Action, and one other I don't remember.
The Eliminator GamePad Pro does not have a solid feel to the directional pad. It's hard to keep it going the direction you want to go, because it's a 360-degree pad rather than the old 8-way pads.
The regular GamePad Pro is the easiest to use, IMO. Definitely my favorite of the four I bought, and I only bought ones that felt decent to begin with.
Logitech Dual Action is also a good pad. My only gripe with it is that the default directional controller is the mini stick below the D-pad, so emulators will ignore the D-pad altogether. There's a software switch you can get to change that behavior so that the D-pad becomes the default directional controller, but it never worked for me. Of course, the D-pad on this one is good, and if you like the mini sticks then this is probably a good controller for you.