No but reading about them, I hear they are amazing. People are using them to drive even expensive speakers and one i've seen is driving $30,000+ Floorstanders; check out audiocircle, has a good thread about what people are driving with with the Virtue 1/2.
I'm actually going to get some too but not at this moment.
Among the too many amps I have is a Virtue 2 with the top-of-the-line PS from Virtue.
It is an amazingly good piece of gear for the price, and - yes, sounding cliche and stupid - REALLY DOES outclass a lot of equipment 2-3x the price. It is the best sounding Tripath implementation I've heard (I've had or heard 4 or 5 others).
On a personal level, I still like my DIY Hypex amp better, though even as a DIY piece it was twice as expensive as the Virtue (so one can imagine what the equivalient retail might be).
My Virtue 2 is sitting unused right now, but each time I DO put it in temporarily, I'm reminded how good it is.
I'm tempted to try the battery PS for it that GR-Research offers, just not a priority right now.....
With a couple friends over a few months ago we tried a little experiment. How did the tiny virtue two with totl ps compare with my marantz sr7001 receiver driving my av123elt525t. Source was the stereoanalog out from an oppo bdp-83. While we had to jet about max it to get decent volume it was about comparable with the $1400 receiver, maybe with slightly sweeter mids even.
I didn't have the amp on hand to compare directly with the musical paradise mp-301 but for $200 I think it's a better bargain. But not nearly as powerrful