Good thread. So I mountain bike a lot, every week no matter what, would consider myself expert level and race from time to time. Like you, each bike I have is worth 5-10K so security and damage are important. Some bikes are lightweight carbon affairs, one is a 55lb ebike. Ive tried many ways to carry the bikes. After 10 yrs of messing about, here are my thoughts;
Option 1. For a hitch rack, just get a Recon Rack. Its expensive, heavy, but does ZERO damage and you can drive like a maniac with that thing, plus you can shuttle your buds all day long. Other vertical racks including NSR and Yakima all have subtle issues. Alternatively if you want a simpler rack Kuat or Oneup are really good.
www.1up-usa.com
www.1up-usa.com
Option 2, use a tailgate pad. The raceface pad (Fox is same design FYI) has expandable width (front to back) which you need for the huge tailgate on the Rap.
Option 3, is the Rockymounts track and driveshaft attachments. This is the most stable and can confirm a 29er fits with the tailgate closed, albeit at an angle. This physically locks your bike to the truck through your front axle. You can go crazy in the truck with this setup. For the ebikers out there, this is the best way.
Amazon.com : Ford F-150 Bike Rack : Sports & Outdoors
www.amazon.com
Then, most importantly, LOCK IT UP! People lift bikes out of trucks at the stop light.
Anyway, hope that helps.