I've owned four different Maggie systems over the years (as well as numerous other systems) and here's my take on the pros and cons. For years, I'd go back and forth between owning Maggies and owning other dynamic speakers, because I'd always find I was missing the strengths of the other kind of system. In recent years, though, I've found dynamic speakers that rival the Magneplaners strengths without their weaknesses (particularly the Revel line).
Maggie Strengths
Cohesive sound from bottom to top
Cleanest and quickest high-end I've heard
Open-airy sound when set up correctly
Particularly smooth and natural upper midrange
Vertical directionality reduces room effects from floor and ceiling
Don't look like speakers
Maggie Weaknesses
Lack of dynamics (this is always what brought me back to dynamic speakers)
Significant loss of openness and detail when played at low volume levels (relates to dynamics)
Weak bass - sounds strained when pushed hard. Can be augmented with sub, but with loss of cohesiveness
Finicky placement - hard to get best bass and best imaging at the same time in some rooms.
Vertical directionality - not as good for parties when everyone is standing
- Jay
http://www.jaytorborg.com