I think you have to go with your gut and do what feels right. A lot of experts recommend waiting till 6 months or later to even start solids. Every baby is different though and you know your baby.
I will tell you that the logic behind giving cereal to help with reflux is that it is thicker and "heavier" so theoretically it should stay down easier. I've heard of peds recommending adding cereal to a formula bottle to help with extreme cases of reflux (although that is generally "against the rules").
We didn't start cereal for that reason, and it could have been coincidental because of the age, but DJ's reflux did get MUCH better at the same time that he started solids.
The bottom line is that you have to trust your mama instincts and do what feels right for you...you're going to get a lot of flack either way so you have to do what you believe is best. Good luck!