I'd suggest Cadence Audio. I bought one of their amps several years ago to power my wetsounds speakers and submurged the thing several times due to stupidity and pulled it out let it dry out hooked it back up and works like a champ. They even said if this was to happen they'd still warranty it. That sold me hands down. Here's a 5 channel at much less than the others and probably just as good if not better.
http://www.cadencesound.com/products/Boston.html