You know you are going to get a bunch of responses primarily telling you what others have and that they recommend them, right?
I traded my 2011 Keystone Cougar High Country, 33'9" double slide rear kitchen for the best RV I have had yet (6 total). Our new rig exceeds our expectations in every way over our Cougar.
The floor plan of the 337RLS is pretty typical these days and offered, in very similar design, by most manufacturers. I found the Grand Design to be well appointed, well constructed and a very good price. The icing on the cake is even with some new buyer issues (and every manufacturer has them), the after sale support by Grand Design is excellent. The weak link in the system is the damn dealers and their service departments. Even if they are the problem on an issue, Grand Design WILL step in and assist you.
Anyway, good luck with your search!
Paul "Poppy" Cervone
2016 GMC Summit White Denali 3500HD SRW CC/SB
2015 Grand Design Reflection 337 RLS