While the first three M&M are now a bit on the older side, 4&5 is what I consider the best heroic fantasy RPG available to date, with a wonderful story that goes from the bright to the dark side of xeen, giving you a really strong and unkillable avatar... until you finish 4&5 and try the bonus Clouds of Xeen dragon where the first dragon will make you totally regret not being a power leveling adept.
MM6, while not as good as its two predecessors would still be worth a full 4 stars on its own, with maybe a half star bonus just for the pleasure of bombing whole cities with meteors. Unfortunately, while it is easy to be a savior, being a bad-ass is very hard, and while I did kill all citizen, I never got under a real bad reputation, which is a real shame.