We bought a 337 in prep for retirement, too. Can't wait. I would echo everything the others have said here. We opted for queen size bed b/c we wanted the shelf spaces next to bed for phone, kleenex, etc. And be prepared, they don't put good mattresses in these units. I think it's because everyone has their own idea of "good" and it's impossible to please each customer. We purchased a 3" memory foam topper for the bed and have been pleased. A lot of folks change out to a completely different mattress. Also, on the sofa bed in the living area, I would unfold it and make sure it is level. It seems everyone has found that the foot part of that bed is significantly higher than where you lay your head. Folks on this forum have instructions to cut down the legs on the foot part, but if I were you I'd see if the dealer would do that for you. Grand Design really needs to remedy this simple problem. We haven't added the bedroom AC but probably will after this camping season. I know that running two AC's requires 50 amp service and we camp a lot of places that just offer 30 amp, so we're still taking the wait and see approach until this season is over. Last year we did okay without the second one and sleeping temperature was never an issue at all. I think if we were in the deep, humid, hot south there would be no other option but having the 2nd AC.
All in all, we are beyond thrilled with our purchase of the Reflection 337. Just couldn't be happier with this unit and I bet you will be too!! Like Bamaman said, the fireplace is amazing!! We initially thought it was just for looks but discovered it is a very functional heating unit. So far the only issue we've had is that our furnace didn't work. It was repaired under warranty and works like a charm now, but we definitely found out how functional the fireplace is before that repair was done.