As I responded in Riley's thread, I really like my MC-1's and feel they are worth every penny of the $750 I paid for them new. One of the better resources I found to learn about Maggies, in general, is 'MUG', Magnepan Users Group at 'www.integracoustics.com/MUG/MUG/'. Search the message boards for MC-1. Also the Magnepan web site is helpful. I have a houseful of in-wall speakers driven by a house system which takes a line feed from my main system. The wall mounted MC-1's are in a different league IMHO, and are the best wall mounted speakers I've ever heard and their look on the wall is stunning. They have a similar sound to their bigger Maggie brothern which I've listen to many times and love.
As far as amps, my Audio Research 100.2 puts out 200 watts into the 4 ohm load. Audio Research and Maggies seem to be a 'tried and true' match and my combination will play plenty loud for me. I am also impressed at how full the sound is at low volume levels. Don't know about lower power amps, but if you want loud I would stick with a high quality, high current amp just like the bigger Maggies need. I did, for fun, hook up an old 50w Linn LK1 and it sounded terrible with the MC-1s.
One more thing, they only entend down to 80 hz I think. So somehow you have to plan for a sub-woofer. My Vandersteen 2wq blends in quite well.
Can only give you impressions of the MC1 since I don't have a HT or center channel, but feel that, with high quality amplication, the MC1's, CC-3 center, and maybe MMG-W rears with a Vandersteen sub would sound great for both HT and 2 channel stereo. Hmmm, maybe I should get into HT?