Hello.... I've been lurking on here for quite some time and now that my focus has changed from my hybrid to a desire to own a road bike, I have questions.

I've been researching the Specialized Ruby and am uncertain on sizing. The info below is from their sizing chart:

54cm 5'6" - 5'8" 168 - 173cm
56/57cm 5'8" - 5'10" 173 - 178cm

I am close to 5' 8.5" which indicates the 57cm frame, but with my height being on the lower end I fear the bike may be too big. I don't have a local bike dealer with these bikes in stock so I can't test drive to see what feels better. I know stems can be swapped out but it would be nice to get a proper fitting bike without doing this if possible. Has anyone else had this issue?

Thanks