I have a new Shamrock 23ws, I previously had a Kodiak the Kodiak mattress was a 6 year torture test even 4 inches of memory foam couldn't cure LOL!
The Shamrock has a heated mattress that has springs etc inside and is actually comfortable and is heated! If you are looking into a mattress for your camper and want just a "mattress" solution order one from Forest River, one thing you could do is go look at a new 23ws and lay on the bed and try it, might be worth looking into, Other than being too small of a camper the mattress was the only complaint I had about the Kodiak.
If you got the mattress I think the heater controller is sold separate. If I would have known there was something I could have bought for the Kodiak (the Shamrock mattress folds so it would have worked as a replacement) I would have got one at least for my side of the camper!
