Figuring out the correct formula

Until recently, we have been having a difficult time finding the right combination between formula and feeding bottles for Mason.  Ever since the first day he began consuming formula, he has been really gassy and fussy.  We tried Similac Advance first which is the general type everyone uses.  But he did not like it, so we thought since Phan has a history of being lactose intolerant, maybe we should switch to the Similac Soy formula.  The results were pretty much the same.  We spoke to our pedatrician who recommended the Similac Sensitive formula.  It helped a little but Mason still had a hard time digesting and kept on grunting at night.  So we finally tried the Similac Expert Care Alimentum formula.  We have been on it for a month and have had positive results.

Some people stated Mason's gas may be from the bottle he is taking.  We have tried just about every type of bottle from the expensive, Tommee Tippee...Playtex drop-ins (which are really easy to use)...Playtex Ventaire advanced...Avent.  But Mason's preference is Dr. Brown's.  Some people may think its too complicated to use, but it really isn't.   There just two extra parts that insert inside the bottle which is convenient and easy to clean.

Mason did not like the regular advance, it gave him a lot
of gas and he was always straining at night.

The soy formula, did not change anything...
pretty much same results.

The sensitive formula helped a little, since it was
specifically directed towards fussiness and gas.

The expert care formula gave the best results and this
is what we are currently feeding Mason.

This is Mason's preference in bottles, Dr. Brown's.