While delamination is a constant issue that keeps coming up on other forums, it really seems that while problems have been reported, there do not seem to be a huge number of delamination complaints on this forum. Some of course, but not that many. So yes Luan and other materials are used, but the Jayco vacuum bond system must be holding up fairly well. Of course the aluminum sided units do not have this issue, but ALL RV`s need to have their seals/sealants maintained to keep out water. I believe if you are vigilant in your regular maintanance, more then likely the luan question will be a moot point.
2004 Chevy 2500HD Crew Cab 6.0l, 4.10r
2010 Jayco Jayflight 28BHS
Reese Strait Line with Dual Cam
P3 Brk controller