My room is 17X18X18, and i had to get larger amps.. I would also recommend getting a larger center channel, either the 160, or 180.. I went from a 135w per channel amp, to 500W per channel amps. The reason for buying more power was that i was driving the 135W amp into the clipping region. You have a lot of air space to fill, depending on what volume you listen to movies, you will benefit from more power.
However, with that being said i agree with John, that it won't "sound" better.. You will just be able to drive the speakers father without driving your amp into the clipping region.
Right now i have 3 amps. two 2 channel amps, and a 3 channel amp... i have 7 channels of amplification because i have a pair of LFR's which use 2 channels of amplification each.
