Wow reminded of this thread. In recent times I have found something hotter than hot stuff. Nicoflex. Some of the guys in my gym were using it and I asked if I could try it out. It's definitely hotter. Capsaicin based like hot stuff but I found you can't directly compare the concentration as hot stuff doesn't list it.
concentration percentages http://www.martialartsplanet.com/forums/showpost.php?p=1074594482&postcount=19 info from their web site :' D LFD
The tricky thing is the hot stuff only lists the percentage of oleracium capsicum. Only a (currently unknown) percentage of that will be the real active ingredient of capsaicin. Other capsaicin based liniments includ nicoflex directly state the percentage of capsaicin used so you can't really compare.
That being said hot stuff is still more than adequate for pretty much all applications. I'm sticking with the tub of hot stuff I got after lfd's recommendation. It will last me a very long time.