groovygamegear still has the key-wiz.
I still like them, but I like that the ipac can be reprogrammed permanently (the key wiz requires a program to reflash the new mappings every time the PC starts)
I switched to hackedxbox360 pads hoping for better compatibility for Steam games, but have concluded that a keyboard encoder reprogrammed to not use the first four default MAME keys (CTRL, ALT, Space, Shift) is the most hassle free interface. It just works for almost everything and for the few things it doesn't work for, the workarounds are extremely simple (see the virtual xbox360 controller thread stickied in the software forum).
I still use a key wiz for some things. I just skip over the inputs for those keys.
It's ok as long as you don't need more inputs than that.