to those of you formula feeding... which brand...

to those of you formula feeding... which brand do u use? How much is it? And where do u find it the cheapest? Does ur bub seem settled on it? Any constipation/wind troubles? Sorry for all the q's... Im interested because im not sure the formula my DD is on is agreeing with her she's quite windy & seems unsettled alot of the time... Thanks to all who answer