I have a 19 and 36. My high noon Mr. Softy and my Fobus (both ordered for the 36) fit. The 19 is just a tiny bit looser in the fobus, but I actually prefer it to the 36 fit.
So like it has already been mentioned - they say one size fits most for a reason. There can always be exceptions.
Good luck finding a rig you like - the G36 is a pleasure to carry