I am using a Mark Levinson 335 with the mahlers, in a 8'(H) X 14' (W) X 20'(L) room, with good results. Plenty of power, amp seems to mate well with the speakers.
I use Classe amps with Vienna Acoustics speakers. To my ears, the combo provides a smooth sound. Speaker cables: Silver Audio "Silver Symphony 48" (www.silveraudio.com). Since Classe is a laid back amp, and the Vienna products use silk tweeters, I like the fast and liquid sound of silver cables. If you are willing to spend serious money, you might wish to consider Classe Omega series.