I've owned A's and C's also. IMHO, pretty much most of these 5th wheels are at the same level of construction "efficiency" as the mid-low end gasser class-C and Class-As. They generally have inferior finishes, although the Puma has a standard aluminum exterior which doesn't suffer from delamination issues and is actually easier to repair.
What I know about the Puma, I know from camping a lot with a friend. His is a 5th wheel. He leaves it stored outside and generally doesn't spend a lot of time maintaining it. He had "typical" new 5th wheel issues - Awning went bad twice, I believe the front support motor failed once, basically minor shakedown issues, but nothing major. Nothing major and it's held up well.
If you buy a new one figure out a what a "PDI inspection" is and plan on spending 3+ hours doing it BEFORE you drive away. That's the best time to find and fix issues. They will have issues, almost without exception - not just Puma, but pretty much any 5th wheel. You'll need to find 'em - most dealers miss something.. Some a lot of something.
Warranty *may* just be through the purchasing dealer, depending on how well Forest River actually funds warranty repairs. And that process of getting a repair approved, parts in, and work started can easily take 30 days... So have that expectation.
I'd absolutely buy a used one if it was well vetted, cared for (roof, at least annual), no indications of water, and I did a PDI on it... I might actually prefer one that way.
I think Keystone builds an "on par" 5th wheel. And Jayco a slightly better one (2-year warranty, factory support).
The only downside that I can think of with the Puma is a wood frame. Most are aluminum framed - and it can be argued both ways. Shouldnt make any difference as long as water doesn't get into it. I think even momentum is using wooden roof trusses.
I reviewed Forest River's responses to BBB complaints
- I can tell you that in my opinion, they are much better responses than what you see from Keystone/Thor - and their RVs are typically more expensive.
Last: The brand-specific forums, even if claiming to be independent, typically don't like to discuss quality issues in a fair and open manner... I think most mods are proud of their brand and for some reason don't want it talked down. You can get an objective shake down via PM'ing people with the same model that you're interested in.