In my experience, REI doesn't really do what serious folks around here would call "bike fitting." They will find a bike that you can standover, that has a frame geometry roughly suited to your body sizes, and they will let you test-ride a lot of bikes. But they aren't going to do real measurements, and they aren't going to change out bars and stems and pedals in order to find your fit.

If you want/need to buy from REI, my advice would be:
1) Do all the competitive fit and wrench science measurements very closely and carefully, and find out what total reach and eTT numbers you need.
2) Go to REI and ride all the bikes that have those eTT numbers and roughly those total reach numbers.
3) Buy the bike that feels the best and that gives you enough room to play with your total reach, saddle height, etc.
4) Schedule an appointment with a FULL fitter for a detailed fit of you to the bike. Be prepared to pay $200 for the fitting and another $200 or so for stem/spacers/bars/etc.

The alternative to all of the above is to buy from a LBS that does REAL fitting. People on these boards talk about "their LBS" as if they all do serious fitting in this way, but I've been to half a dozen LBS's in a total bike city, and NONE of them really seemed interested in fitting me properly, even though I told them this was what I was looking for.