I own Rapha, Castelli, 7Mesh and Assos bibs.
Rapha Classic are the most comfortable to the point of being luxurious. Rapha Classic are $230 while PI Black are $250 so price is competitive. I don't like the Pro Team as much as it is more restrictive but that's just my preference.
Winter bibs knickers and bib tights are Castelli. Performance in extreme weather is outstanding and comfort is never an issue. Size way up.
7Mesh MK2 and MK3 have a super plush Elastic Interface Space 2 pad. They are not for very hot weather but are super cushy for long gravel rides, like riding on an overstuffed sofa.
Assos Mille are the lower end models. I've never had a problem with these. The front is cut a bit lower than most bibs so nature breaks are a little easier.
I've never had rubbing or chafing issues with any of these. If I had to choose one however, it would be Rapha Classic without a doubt.
-Tim-