I found the chamois in the core ones to be really inferior to the non-core ones. Pretty much everything about the core ones paled in comparison really, for its price point.
Non-core cargo bibs are my favourite set of bibs I've ever had. Not great for summer though, not super breathable.
I have a few pairs of new PT bibs that I have not used yet due to being so unhappy with the core cargo...but this gives me some hope in that they will be more comfy.
I did 190km this weekend on my Core cargo bibs and they were not comfy.