Maggies...DEFINATELY.
I own MLs, but I still consider myself a maggie guy. they are a little smoother sounding, IMO.
the MG12 is a fantastic speaker, and still in production. Mate that with a small sub, like an 8" model (dual drivers would be nice) and you'll be back in MSG in no time! Even the MMG will blow your mind (and is easily had for $400).
two subs is the way to go. You could get the MMGs and a pair of 8" subs and probalby stay in your price range. You needn't spend a fortune on the subs, just stick w/the smaller models as they are quicker than large ones, and this is important w/pannels (quick sub).
as far as clarity and transparency, the Maggies do this particularly well. the MLs are the king though. this can work both for and against you as it will bring out the best/worst of your componants and sources.
its a funny thing, you'll find a lot of your favorite AUD recording actualy suck, and many of the ones you thought were "eh" are actualy masterpieces.
One thing with panels, you need to have some breathing room. If you can't pull them out into the room at least 30" and several feet from the sides...then you might want to reconsider that direction.
Another downfall is that they only produce a sweet spot suitable for one person. so there is only one good seat in the house where the music comes into real focus. This spot though...you'd have to spend way more money to get that sort of quality from a box speaker w/a broad sweetspot.
you say you may be buying your whole system....sans CD player. the CD player is very important here...crap in, crap out. what is your deck? does it have a digital output?
Those mosiacs you listened to....
go back and listen to a pannel (as the mosiac isnt'). for shits and giggles...listen to the Ascent. I'm sure they'll have one. I assume you went to a tweeter?
Then you'll know what your after.