You are not wasting your money by going surround.
I just picked up just a 5.1 system and hooked it up a short while ago and having never gamed in Surround sound before was absolutely and utterly blown away by the amount of awesome.
The opening scene in MGS4 in the Middle East was 300 times better than with flat stereo, hearing the rockets and bullets zing past...just get surround sound already dammit and see what I mean.

Proud Sony Rear Admiral







