Is that what you were asking when mentioning internal mounting, bolting thru the floor of camper verse external (external being any system using tiedowns between camper mounts and truck mounts).
So we're comparing apples and oranges and your talking pears...
sorry- probably wondering, if thats the case, what are these guys going off about..I at least made your question fit my familiarity:o.
'cept for bcbouy. Which myself not knowing anything about bolting thru floor his comment about ease of removal would tend to make me think more suited to semi permanent mount? I guess depends on how the bolting is done-and how camper to be used. Interesting...
Edit:I just did a quick peruse of the trip camper reports thread looking at pop ups, and all that I could see were/are running 'external' tiedowns. Adding 'PopUp' to title of your thread might yield more response from folks who have them and reasons they went with what they are running. Looked at 4Ws site theirs is outside of camper but attaches to truck floor. Couldnt get on Outfitters, sites been hacked.