I tried to solo him with my shammy. Anguish-ish gear, 1200 aa's. I beat him but it was TOUGH. He didn't catch his exact max hit, but it was somewhere around 1400-1500. And he hits FAST. He was hitting faster slower than a lot of mobs do unslowed. Speaking of which, he was no problem to slow. His resists and hp seemed a little boosted from regular version but surprisingly not very much. His AE was a big surprise... I had around 450 CR so I expected it'd miss most of the time. It hit me all but one time, but it was never a big problem. It only did around 2k damage and it was NOT dispelling buffs. That's the important thing. He did not dispell at all.
Anyway, I'd rate him a little harder than an rss named. If you can take them reasonable well, you can take him. Enjoy 40% haste without raiding or spending 200k.