Krestreldude, my girlfriend's about 5' 1" so she should fit the same bike your girlfriend does.
She tried the giant OCR's (which I believe have the same frame as the FCR's) and S was just good enough while XS was comfortable. In the end, she bought a specialized dolce elite in small and it fit pretty well (since it was designed for women in the first place).
Have you tried looking at the specialized sirrus bikes? Your gf would fit an XS really comfortably.
