I used BEL 1001 monoblocks with my VSM-MX's for quite awhile and was very happy with them. They are much better as mono's than single stereo, with better bass articulation. I also have Odyssey Stratos Mono SE's and this is a nice combo too, though slightly less transparent/detailed and not quite the clean bass definition of the BEL's. The best I've heard on my VSM's other than the Joule VZN100's is a Bella Extreme 3205 Platinum tube amp from Response Audio. Amazingly, it's only about $1k. Something about the little 40wpc PP tube amps that just works very well with them. Lovely combination.
Tom
Tom