The Heat 76 was the Cool Heat before (I think), and I have the Red Heat, which was a step below the Cool Heat in that line. I like my skis, but they are a bit heavy with the system binding. I am actually half shopping around for a lighter flat ski with just a bit more width that is still stiff, probably a sidewall construction. Been looking at the Watea and others, don't know if I'll buy this season.
I'm quite a bit bigger than you at ~225lbs and still find the Red Heats to be a bit ponderous in bumps and trees. The Cool Heat/76 might be lighter than the Red Heat, though. I will say that I found the Red Heats to be an excellent value.