We’ve come from 7.5m coachbuilts to a 6.4m PVC (I think we may have struggled with the leap to a more convenient 6m with the 2 Whippets and my armoury of outdoor cooking gadgets!). Interestingly, thanks to the rise of drop-down beds, 6m coachbuilts are a growing trend. We considered one from Burstner, very spacious!I agree that the bigger motorhomes are certainly very expensive but in the used market before the pandemic I looked at a smaller camper and decided that I was better sticking with a coachbuilt.
My problem was that for ferry travel I had to stay under 6 metres and there are not many coachbuilts at that level.
Incidentally Corran Ferry are now grading motorhomes and campers according to length which they did not do before. Makes sense but if my Peugeot Partner was converted I would be penalised. I have a blue badge and do not pay for a car anyway on this ferry but with a motorhome I don't know how they would work it.