That sounds about right chefdc1. Although I agree that repairing the bunk floor usually means getting at the bottom of the rails.
I wouldn't be surprised if most shops don't use Eternabond for insurance reasons. As-in, install non-OEM repairs and their warranties won't cover it. Plus, there isn't really an advantage to changing a low cost option you know works for a more expensive one that promises no return work.
I liked using Eternabond and it looks good so far. There were a couple of small areas where I didn't get it pressed down hard enough and had to go back to really mush it down. Then it stayed put. The big thing is to use a METAL roller. Anything else doesn't create the mechanical bond you need for Eternabond to set. Once it sets, it is NOT coming off.
Jose