I know there are a few other campers here, so I wanted to pass on something I found a couple nights ago. Our travel trailer has a RV Short Queen size bed and the mattress is craptastic to say the least. Upgrading to a regular queen isn't an option because the door is at the end of the bed and it would limit the walkway.
I've searched locally but couldn't find anyone besides Camping World that sells them. CW doesn't have any on display to try, except for a 12"x12" sample, and as soon as you buy and open the box it becomes non-returnable. I can't afford to spend $500+ on a mattress and then not like it.
There's a company in Longmont and Boulder called Verlo. They manufacture their mattresses in Longmont and can make special sizes. I went last night and ordered a middle-of-the-line plush mattress called V3. It's a little more than I wanted to spend ($700), but it should be very comfortable. They have to order the fabric top from Chicago, but will have ours ready in time for Memorial Day weekend.