Any more updates on how this amp sounds?

How much heat does it generate vs other ARC amps such as VT100 series and VT200 series (or others as a frame of reference).

Anyone run this with Maggie 3.6s or other hard to drive speakers?

The tube compliment is the same as a VT100mkIII with eight 6550C power tubes and four 6H30's, so the heat is exactly the same.

The power is spec'd at 120 watts per channel which is a tad higher than the VT100 series amps, but the supply has a little less energy storage. Subjectively this amp has a better grip than the VT100 mkI, II, or III. I can't comment on the Maggies with this amp specifically, but ARC amps tend to do very well with them.

I'll let someone else comment on the excellent sound because I am a biased ARC dealer.
I just saw your request, I may be to late to give you any help. I use a VT200 to drive my Maggie 3.6's and love it. Absolutely no problems. I have used 3 other amps 2 SS and 1 tube and the VT200 is noticably smoother, with a larger more layered image. The speakers disappear. They are set up in a dedicated room in my basement. The room is always cool in the summer or winter and the extra heat from the 16 6550's is welcome. I can see where it could be a problem in my living room. I hope this helps.