Not yet mentioned here is that some find Maggies lacking in low-level dynamics---the ability to go from 0 to 60 in 3 seconds, as more dynamic speakers appear to do. They need to be listened to at higher SPL than other speakers in order to "break through" what is called the "Maggie Mist". At lower volumes, Maggies sound slightly veiled, thick, and slow to some people. That is less true than it used to be, with improvements to the basic magnetic-planar design Magneplanar has been using since the early 70's.
Planars---all of them, not just Maggies---sound very different from box speakers, even one's with as "open" a design as Vandersteens. Some people prefer planar sound to any other, but one doesn't know if that is true of himself until living with them for awhile. Some listeners tire of the planar sound, missing what dynamics and horns do better. As with everything in hi-fi, one must discover his own personal priorities in music reproduction, and find products that excel at those. Magnepan offers a 60-day trial period for their $650/pr MMG. That's a great way to find out if you like the Maggie sound.