I'm using Brocato Cloud 9 Hot shapes(by the way Brocato products are the BOMB).
I've also used Mizani ThermElastic which is good also.
Elasta makes a good one also but I can't think of the name right now. Hope this helps!!
I use the Fantasia one. I've heard Redken Heat Glide is good. Also, I've used the NTM one in the past and it was my favorite. It's hard to find though.