I've been doing 10 on my really super crappy 30k turkey fryer burner. But with those you have to modify the timer so it stays on, zip ties work well.
But I also have one like Chris linked from CT for my HLT on the gravity stand , and they do work pretty well, and they are much cleaner burning than those cheap turkey fryer setups. I am going to get rid of it fairly soon though, cause it turns my kettle black every time I use it and go with something better.