Budget? Are the speakers 2 or 4 ohm? In any case, it seems as if any amp that can do a clean 100 watts into each of the 4 channels (100x4) @ 4 ohms will be your best bet... assuming that all of your speakers will be 4 ohms each. As for the max ratings... ignore them lol. You'll also want at least 2 of the channels to have a LPF (low pass filter) so that you don't feed those subs anything higher than they need.
EDIT: Here's a solid choice, but just a suggestion. http://www.amazon.com/Lanzar-OPTI100...1256055&sr=8-3 Generally, I'd never recommend Lanzar, but the Optidrive line is well-respected in the car audio world (I was surprised too lol).
