Help on 5ch amp decision

I'm looking for suggestions on 5ch amps for my system. I will probably try to buy used and would like to stay under $1K. I'm running 5 NHT SB3s and an SW2Pi sub. The preamp is a Sony TAE9000ES. I don't want the sound to be too bright and I'm more concerned about it sounding good/accurate/natural on 2-ch music (or SACD/DVD-Audio once I go that route).