Thanks everybody...slow to reply, I know...it's been busy here. DH went away for four days, and I discovered what a challenge it is to be alone with the boys 24/7!
I changed how I'm mixing Simon's formula...I stopped sterilizing his bottles, so I started mixing it up in big batches in a big measuring cup (I used to put formula in the bottle and shake, as directed on the formula can). That has helped some, but he's still really gassy. I'm wondering if soy formula might be the solution...he has a permanent red ring around his anus, and I've read that can be a sign of a milk allergy. I mentioned the gas to our doctor but she just said that was normal for some babies.