Audio Research VM220 tube monoblock amplifiers


There is zero information on these monoblock's here on Agon.
Anyone heard them yet? If yes, what are your impressions?
Associated gear you heard them with?
How do they compare to other large tube monoblocks?
perfectionist
http://db.audioasylum.com/cgi/m.mpl?forum=amp&n=62731&highlight=vm220&r=&session=

Here is a thread comparing the VM220 to the VTM200, still not much helpful information
I had the same problem when I wanted to purchase some. I went to California, a 2000 mile plane ride, to check out some used ones, which I bought. They seemed a little muddy initially, the sellers had told me the tungsol kt120 tubes were brand new, so I bought them anyway, thinking the tubes just needed a break in. They arrived on Friday of last week, and Sunday night, the tubes had broken in, and they sounded, and still sound, spectacular. Bass is incredible. Soundstage is the best I have ever heard. They just sound so right. They control the bass panel on my Magnepan 3.6 so much better than other high powered tube amps. They are exceptional! I am glad I bought them, and took a chance that the tubes really were that new. And they were. Dave Gordon of ARC told me they put everything they knew about building tube amps into them, I cannot doubt this for a second. He also said that they were discontinued simply because they weren't that hot of a seller, people opted for the cheaper vs stereo amps, or they financed a pair of ref 210s. So, since they didn't move that quickly, they were discontinued. He also said they were an incredible bargain on the used market, and I agree. They're also so much nicer to look at than the ref 210s, so much prettier... I love having them in my living room! I have listened to them for 5 days solid now, maybe I'll work tomorrow. One thing is sure, I will have these a long time!
I paid 4k for a pair with only 150 hrs on them. I am very happy with the sound. Does anyone know how high you can tweak the bias ma on the stock 6550 tubes? Manual says 65 ma. What is a safe setting that gets you a significant change in sound but still gives you reasonable tube life. I set my bias at 68 ma. Should I hear a difference or do I have to go higher?
Set the bias for 65mV that's it. Going higher buys you nothing except decreased tube life. I tend to set em a bit lower actually like 63mV.
Do you get a change in the sound at 63, or are you setting things low to get more tube life?