I bought the force products one, hustle sells them as well. Yes it's made of polymer, but it is solid and I can't imagine breaking it. Many people see polymer or plastic and immediately think worse quality, which is not always the case. (edit: the python one is actually also plastic, but uses an aluminum clamp...meh)
It also uses brass threaded inserts so you won't be stripping the threads easily. It doesn't require removing the hook, either, as mentioned.
I didn't get mine to attach a hopper, but to mod a spring feed to my phenom for use in magfed/spring fed only games w/o having to get a magfed kit and replace the clam shells while allowing me to swap back to the cyclone in a matter of minutes. I paid $30 which is a much more reasonable price to perform the same function and at(imo) the same quality
edit2: the only thing I like better is that the python one is more rounded instead of boxy, but that can easily be modified. I haven't seen the python one in use, but hustle does have a video of the force products one, and it worked well with a rotor, so it feeds well.
Last edited by Skywalker; 12-09-2012 at 05:29 PM.
Reason: correcting info