From a white board perspective, Astro-Foil insulation is much better then traditional fiberglass. Mostly because AF will NOT hold moisture and helps repel critters.
For more details, surf: http://www.astrofoilint.com/stage/products.html
For my next Dream Trailer that I plan to keep for many years, I'd focus on a Build Design that uses Spray Foam. I applied Spray Foam under my Jayco's floor and am very impressed with it. To me, Spray Foam should be used in Jayco Eagle models as well.. Perhaps in time...