I need a new power amp (the one I currently use, a Carvin FET1000, is borrowed and the owner wants it back). I'm looking for around 500w/channel at 4ohms and around $300-$500. The amps I've been considering are Crown XLS602, QSC RMX1850HD, Carvin DCM1500, and Peavey PV1500. I use a Sansamp RBI preamp and Avatar 210 and 115. Any thoughts on these amps? Any other suggestions?