I just pulled mine out and put in a Ikea spring frame. I need to finish writing up what I did and post pictures. I did move from a RV King to a standard queen so I did lose some bed area but picked up a bunch of floorspace in return. Weight was about the same.
What I've not figured out is just where to put the gas shocks to help lift the frame. That will be a project for later I think.
I've seen several others discussing the 2x3 frame giving out. I think the discussion is in either the Kingston, Cruiser, or Modifications fora.
Al & Linda
2013 GMC Denali 3500HD SRW, Crew Cab, Std bed, 6.6L Duramax, Allisons, PullRite Superglide, Triglide
2011 Crossroads Seville VF35CK11