Quoting lolajessup:" Doesn't it take longer to pump and bottle feed? Just wondering cause it just seems like more of a pain. You will probably lose your supply fast by just pumping too, something to think about."
I hope she doesn't mind me answering for her... i know she really wasn't asking for opinions on how she is doing it, but I also ended up exclusively pumping. It does take some extra time, however if you have other support people available they can take over a few of the feeds which relieves the mom a bit and gives her boobies a break. She can keep her supply up just fine if she is dedicated to pumping on a regular basis.. which I did just fine for twins.
Anyways to answer the original question... if you have already started with one formula and it's working for you and baby then I would stick with that one. It is hard on baby to switch back and forth with different formulas, especially on top of the transition from exclusive breastmilk to introducing formula.