Has anyone tried this or any carnitine in any form of supplement?

I'm curious what your individual responses are, I've always been pretty skeptical about it but had the chance to grab it for a bargain price and I don't regret it one bit, I can only speculate why but as low as 500mg it's helping a great deal with my chronic asthenia by providing almost sub-normal (though short-lived) muscular responses, I can also feel much more heat generated even with light exercise.