The 150 series Reflection needed to be lighter weight (to appeal to F150 owners), so Grand Design went with a laminated floor which is a Styrofoam core sandwiched in luan. If you go watch factory tour videos and they are building a 150 Reflection, you can see this anywhere they have cut holes in the floor for cable, water lines, etc. Use Google to find out how this floor design has worked out in the past. As you walk on it, the foam compresses so you end up with soft spots in high traffic areas over time. IMO, not intended for full time use.
FULL Reflections (models starting with a "3") have the same floor as Solitude, it is a one piece OSB floor product called Dynaspan. The pros are the sheet can be made in any length so there is zero waste, with it being one piece there is no chance for squeaks between the different panels like with plywood. The downside is, there is uncertainty about how it reacts to water intrusion especially at its edges. I found the company that makes Dynaspan and downloaded all their product papers and in all their shipping to manufacturer info, handling info etc they stress over and over to keep it away "from moisture". When building a home, your contractor picks whether they want to use OSB for the subfloors of your home, or plywood. Traditionally, plywood was preferred because when it got wet it would swell but would return to its original shape when it dried. OSB wouldn't. SO, if you put down OSB subfloors and it rained before you got the house dried in (the roof and walls up), then the contractor would have to pay to go in and sand down all the joints of the OSB floors to make them level before putting in the flooring. To combat this, a company (I can't think of the name) came up with a product that was improved in that area, and they even made it part of the "warranty" that if the edges swelled and needed sanding, they would pay for it. It is quite a bit more expensive. How does Dynaspan compare to that product? I have been unable to find that out. This is ALL the info I have to share on that subject, it is incomplete but moves the ball forward. The OSB in the floor (and roof) does not concern me too much (I would rather have plywood), but the foam core floor on the 150 is a deal break for ME. But, I am needing a full time rig and I weight over 250 pounds so my needs are specific to me.
To be honest, Grand Design not using Azdel in the walls (they still use Luan), them using pinch rolled lamination instead of vacuum bonding, and them mixing in some 1/2" vinyl hose in the plumbing which they use PEX clamps and fittings on (not size compatible so they are prone to leak) are bigger concerns. The rest of the industry is also finally moving away from Schwintech slides even for the bedroom slides and GD needs to as well IMO.
BUT, show me a single manufacturer that does everything right. Alliance also pinch rolls, uses foam core floors in their Avenue, and their rear walls are falling off. Pick your poison. It is like all of them get together and make sure that every one of them does SOMETHING in their manufacturing and materials selection that is a terrible idea. I am saddened by how many people on this forum are surprised and upset that their cabinets are not actual solid stained wood, but rather are a vinyl sticker wrap over a MDF/paper like product which is layered on the front and back of actual wood. That sticker comes off and it looks really bad. Water leak in a cabinet is really bad news as that paper/MDF layer falls apart. But they do that so the sticker has a smooth surface to stick to so it looks better. They use a sticker because using wood suitable for staining, then sanding and staining that much cabinetry would drive the cost of the unit beyond where Grand Design is priced (except maybe Solitude?). Weight is also a concern.
