Rapha, nice but a bit pricey?

I am 6ft, 65kg 29" waist and have a pair of large Assos bib shorts which fit and a medium pair which also fit (both S5 Uno)
The medium is a bit more snug, but both the straps and fabric have a good amount of stretch (much more so than other bibs I have)

Tights may have a bit less stretch if the fabric is thicker though...

I have Assos 3/4 in M, I am 5"6' 64kg 30W and they fit fine.