Amp s for CLS IIZs

I'm running a set of Martin Logan CLS IIZs, and am looking into an amp upgrade from a Threshold Stasis III. I tried VAC V-100s (100 WPCH) on these speakers, and the result sounds excellent, but it runs out of gas too soon, and the tube life was unacceptable. At this point, I'm looking for a set of Bryston 7B-STs - the warranty will last until I'm over 60 (past the point of beginning lunacy), but before I commit myself, are there any other low maintenance ideas? I want to do this once -

I listen to classical, jazz, newage, some folk, and old classic rock, such as Jethro Tull, Moody Blues, and Alan Parsons Project.