I live less than 5 minutes from I 79 and always take I 79 to Route 19 to I 77 to I 74 Route 52 to 73/74 to 74 to I 95 to Route 9 into North Myrtle
All good roads 4 lane highways for the most part. Traffic can get just a little heavy in Winston Salem but it keeps moving no delays.
Depending on where you are staying in Myrtle you can take Route 9 straight into North Myrtle (good for Myrtle Beach Travel Park) or get on Route 31 which is a four lane bypass which will take you south to Ocean Lakes, Pirate Land or Lakewood.
The only big gotcha is coming home on the weekends you will get stuck at the I81 I 77 merge if you hit it in the afternoon. I'm talking complete stop and crawling a few feet at a time kind of stop. Everyone coming north from Myrtle Charlotte etc just jams the merge point. We solved this by traveling home during the week.
Regarding campgrounds there is a decent park in Wytheville called Fort Chiswell RV Park. This is definitely an overnight stop but very little if any highway noise has a small pool that was nice. There is not much in the area as far as tourist attractions or fancy restaurants but you can get a good nights sleep there. I highly DO NOT recommend the KOA there. Stayed there only once and it was miserable. Electric hookup was so far away in front of site that I had to purchase another electric cable just to hookup. Staff was miserable and guys riding around in pickups making lewd comments to my two daughters.
PM me if you need more details or have questions
Dave
2013 2500HD Chevy LTZ 6.6 Diesel Ext Cab Long Bed
2017 Grand Design Reflection 27RL 5th Wheel
Dear Wife, plus two Cocker Spaniels and a Standard Poodle