Some of the unanswered questions on the spray in bedliner:
1. I have heard it described as a "factory" bedliner. If so, this implies in my mind that it comes direct from the factory, and it is not the dealer taking it down to the local Rhino-liner or Line-X franchise to apply. Full factory warranty implied as well. Intuitively, I would think a factory controlled environment during the manufacturing process would offer the best application, but this may be one area where a good, experienced installer gives a better result.
2. Is the "factory" bedliner from one of the major suppliers like Line-X or did GM develop their own system? (If one of the major suppliers, I would expect them to be advertising they were chosen.) Thickness, chemicals used, etc. could all be an issue. But I also would think that the 6 year/ 100K rust warranty would be voided by an aftermarket application.
3. Cost of the factory option versus going down to the local liner supplier yourself. (Factory option on short bed Silverado is $475.00. I believe that cost is comparable to a Line-X dealer install of standard version and well worth not having to deal with half a day getting the bedliner installed after the truck is delivered.)