I've driven MMG's, SMGc's, a MGCC1, and most recently a pair of 2.7QR's with Rotel RB-981 amplifiers (170 watts/channel @ 4 ohm). Even with the most power hungry of the bunch - the 2.7's - I can't really complain about the sound. All of them have been in what I consider smallish rooms (no larger than 16 x 16), and I've never ran out of legroom on the Rotel before my ears wimped out.
I do suspect, however, based on where my preamp gain is at the loudest comfortable listening volumes, that in larger rooms with more acoustic damping (I have none currently), the 981 (or current model 1070) would probably be a bit overwhelmed. When I move into the new, larger theater room (30 x 20), and step up to 3.6's, I plan to biamp using a pair of 991's (or 1080's).
As far as "sound," well, I personally have never believed that well designed solid state amplifiers can be distinguished when listening through most any speaker you can find (based on my experiences in blind testing). I do think Rotel mates well with Maggies for a couple of technical reasons though... high damping factor (probably not that important), largish capacitor reserves, and beefy torodial power supply. Rotels, for their price, do a pretty good job at delivering lots of current when required. I think a Parasound, Sunfire, Bryston, Sherbourn, Outlaw, or similar amp would probably do the job equally well, but since I started with Rotel amps I suppose I'll stick with them to keep things looking all nice.
What speakers were you interested in mating them with? From my experience, I'd suggest the following as a rough (and I emphasize rough, since it is highly room and preference dependent) guide for matching current Rotel models (minimum amp I'd use) with current Maggie models:
MMG - 1070
MG12 - 1070
1.6QR - 1080
3.6R - 1080
20.1 - 1090
If you wanted to be absoutely sure you had enough power, you could step most of the amps up a notch:
MMG - 1080
MG12 - 1080
1.6QR - 1080
3.6R - 1090
20.1 - 1090
These suggestions are based on current requirement, and are highly dependant on your preferences. For example, listening to soft jazz and vocals 100% of the time would probably only require a 1080 for 20.1's, or a 1070 for 3.6's. The rule of thumb with Maggies though is to have as much current capability in reserve as you can afford. Rotel is a reasonably economical way to accomplish that.