Is this stuff any good? I'm trying out the one for SUVs at the moment, which treats up to 35 gallons. Locally, the only American ones I've been able to find is Prestone, CRC, STP, Gunk, Castle and something else I cannot remember at the moment. No Chevron Techron or anything like that. The CRC looks very impressive, but it's more aimed towards passing emission testing from what I gather. I cannot really comment on the rest. STP is actually sourced from the UK and other than that, there's nothing much I can say. The only thing I know is most of these treat up to 16 gallons, and I have a 25 gallon gas tank...so I'll be needing 2 bottles for anything else other than Prestone.