My doctor talks through the step-by-step process during a PAP to ease the tension, and while he was explaining that the extra pressure I was feeling was from the speculum I said that it didn't feel much different than inserting my menstrual cup, to which he didn't bat an eye and essentially agreed it would be a similar feeling. So 1) He knew about menstrual cups and 2) Had no serious opinion of them.
I hope this was helpful to at least someone out there! Also, if you have a similar story (or entirely different) I would love to hear it in the comments. I'm still interested in the different viewpoints doctors/nurses have on cups.
edited for easier reading