Hi-Fi wanna-be needing advice on an Amp purchase

The Hi-Fi bug has bitten and I'm looking to upgrade my Yamaha receiver with a quality amp at a Mid-Fi price (under $1,000). I currently have the Paradigm Reference Studio 60s that are poorly driven by an under-powered, awfully bright Yamaha receiver. For the time being, the Yamaha will remain in the configuration as the pre-amp. Through my local dealers, I've been courting the Adcom 5500/5503, Rotel RB-1080 and the Anthem MCA 20. I had a weekend test drive of an Anthem MCA 2, which convinced me I needed to upgrade, but now for a decision. Any advice on great amp match-up for Studio 60s???