I’ve just gone through this (180cm) and comparing the dimensions to my current bike I should get a L. However, the sizing guide has me at M. It’s worth doing the online guide 2 or 3 times. If you’re comparing bikes Reach and Stack height are the important dimensions to compare rather than traditional numbers. I don’t think the headtubes are that short so with spacers I doubt you’d find the drop too much. If it is there’s always compact bars. A 115mm stem would probably sit better on the M if you want to keep handling similar. Check the rake of the fork also.
The trend certainly seems to be for erring on the side of smaller frames in the peleton (if that bothers you). Phil Gilbert is 6ft and rides a 51cm frame!