Paradigm Studio Ref. 100s...
Kirklin,
I think the basic answer to your question is that the more power capacity an amplier possesses, the greater the possibility that it will not have to be driven to it's limits to reach high volume levels, thus providing cleaner power output. You may not hear a difference between driving your speakers with a 150 Watt / Channel amplifier vs a 200 or 250 Watt / Channel amplifier, depending upon how hard (loud) you are attempting to drive your speakers. That said, any of the amplifiers you listed should sound great with the Paradigms.
When I was listening to amplifiers / receivers before purchasing, I did have the opportunity to listen to a large Denon, Yamaha and B&K Home Theater receivers, and found that I preferred the sound of the B&K the best. It didn't have as many bells and whistles as the other two units, but I thought it sounded cleaner and more open. I think it's something you're just going to have to experiment with, given your ability to line up the equipment for testing....
By the way, I have the Studio Reference Series 100 V3s, the V3 CC-470 and V3 ADP-470s, and love them.
Good luck,
Pat