There's only one Interact product I've ever been really satisfied with, and that's the most famous one made by Datel, the Playstation Gameshark version 2. Every other Interact/Performance/Recoton video game product I've used, with the exception of an N64 RF switch, was crap (Quantum "oops, you can't remap the L and R buttons to the two extra front buttons" Fighter Pad comes to mind; guess which one of my DC controllers got sacrificed when I wanted to look inside one...). I suggest avoiding them if possible.
Mad Catz, in my experience, makes better stuff, though some people don't like their controller designs. However, Mad Catz products aren't available in as many places. I think they make a DC light gun, but IIRC the styling is kind of strange - it looks like something out of a sci-fi movie.