I had to decide between the MMM and MGM a few months ago and ended up with the MMM. It's cheaper, much easier to get support for, has better support available, etc.
EDIT:
http://www.rc-monster.com/forum/showthread.php?t=18336 That's the thread. I wouldn't buy a Quark, myself, they have a bad reputation for overheating and even catching fire. Considering what you pay for a MMM I don't think you can get anything better.