Oddly enough, the best blowjob I can remember having was from my 16yo girlfriend when I was a horny 15yo virgin. She had this interesting technique of swishing around her spit and using her tongue. She also had an enormous mouth so that might've been what did it. That, or I was just so fucking excited to be getting a blowjob that in retrospect it seems better than it really was.
But that might not be, because I also remember her having the loosest vagina I've ever done battle with. And awful odor, which is twice as bad when you're in the backseat of a Toyota Camry. I used to just bear with it, breathe through my mouth and desperately pump away because when you're 15 and stimulated, no blow = blue balls. And then you end up having to pull over on the shoulder on the way home, pop in your sister's My Little Pony soundtrack cassette tape and beat your meat until your nuts stop aching. It all works out, however, as it gave me some extra time to air out the car and get rid of the girlfriend's awful essence of rotten crotch, and also make sure she took her panties home.