I use Conrad Johnson Premier 12 mono block tube amps (140W side).The combination works great. The Perspectives are supposed to work well with tube amps even though they aren't very high sensitivity, due to their benign impedance which tends to stay above 6ohm.
That said, I still think the Perspectives benefit from an amp with power and control. They sounded most "in grip" with some powerful SS amps.Fortunately one of the great aspects of the CJ Premier 12 amps is that, for a tube amp, they have excellent punch and control right in to the bass region.
The other tube amps I heard with the Perspectives were Mac. 75W I think. Sounded amazing, though with a bit more bloat on the bottom (which could also have been due a bit to room placement at the dealer).