I find it strange that your pedi is so against changing formulas if he's gaining so well. But, I also don't know about the reflux formulas and if they actually help. Alexander had a dairy intolerance as well as reflux and when we got him off Neosure (and onto a soy based formula) he felt much better. Neither of my boys could tolerate Zantac. It made Jonathan vomit more. We've had good luck with Axid (and Prevacid for Alexander when he was older). If it were me, I'd push the pedi (or talk to another GI doc) more because I don't think it's fair to keep a baby in that kind of misery without trying some other things.
I forget how old he is, but is he on solids yet? I gave my boys cereal at 5 months and always before bed so there was something a little thicker in their tummies before they were laying down. We're still waiting for Jonathan to outgrow his - fortunately, he's a "happy spitter" now.