To be honest, I think fuel additives in general are a joke. How much good do they really do? Don't you think it's maybe the psychological aspect that makes you think your engine is running smoother? Like all those weight loss infommercials... the appetite control programs. The only reason your not as hungry is because you tell yourself that you can't be as hungry as a justification to the absurd price you just payed for the bottle of 30 capsules. Same goes for the pills that magically create better sex.