New York City (unfortunately, I don't think there's a Performance Bike around here). I'm looking for 48-50cm.

Very helpful to know I should be looking at 105's - Tiagra, so thanks for pointing me in that direction.

I'll check for upcoming sales at my go-to LBS's with all this in mind, test ride a few, and we'll see what happens. I have a much better idea of what to look for after reading the comments here -- thanks!