Bryston vs McCormack, any thoughts???

Both are very dry, bright and the Bryston can be unstable at low impedances to the point of clipping. If amps were medical instruments, these two would be ice cold scalpels.
great specs , but no human warmth nor musicality.
I am now running MF mono blocks on my Maggies and am in heaven. Very sweet, tube like sound, but great bass control, open, slightly forward midrange and pleasing high end without all of that high end brittleness that is so commonplace today.
You may also want to demo Classe and Stratos. I've heard good things but have no personal exp. with them.
Also consider a tube preamp. Makes all the difference in the world unless your goal is to try to hear all the recording defects on a CD in which case the instruments, er,..amplifiers you mention above will be fine.

For the record, in response to Sv47's comment about the Bryston 4BSST being unstable at low impedences:
I've had this amp hooked up to several speakers in the last year, all sub 89 Db sensitivity, all 4 ohm or lower (the dynaudio's spend most of the curve under 4) and the amp did not clip, instead it's taught me the meaning of microdynamics, headroom, and pace.
It also cut more than a few discs out of my rotation!
This amp has shown me what's really on all these discs.

I would be afraid of the conditions under which this amp would clip!