....is this a better option coming off the M5 and going A38 through Plymouth to Pentewan, Cornwall or do i go the M5 then A30 which seems to be the busiest road and has roadworks. It will be our first long trip with our van and starting to get a little bit nervous towing all that way from Yorkshire.
I'd say A30 - the road improvements affect the crossing road more than the A30. A30 is a good route to Cornwall, while A38 can be a bit "wacky races" at times, less lanes and more navigation to do through Liskeard etc.
I would use the M5 then A30, most of the bad hold ups seem to be after where the A38 rejoins the A30, also the Tamar Bridge can be a bloody nightmare. To be honest, you just have to accept that you will hit some traffic at some point en-route to Cornwall.
No need to be nervous tigger....by the time you get anywhere near Plymouth you'll have wondered what there was to have been nervous about in the first place. Just nice and easy down the hills and watch out for the couple of places where you may encounter crosswinds if it's breezy at all..
You could always do a Wednesday to Wednesday at Pentewan, lots less traffic until you get off the A30 going into St Austell but you could always get around that by timeing your arrival for 0900 plus you wouldn't have too long a wait for your pitch.