Hi urnmor,
The better options or possibilities I’m aware of in the Ocean City area are listed in post #2 here but there aren’t a lot of good options available in the immediate area.
As you probably know Rocky Mountain Mattress is one of the members here which means I think very highly of them and I believe they compete well with the best in the industry and they do make RV mattresses so they would certainly be well worth talking to. Some additional online options I’m aware of for RV mattresses are listed in post #2 here.
There is more about the most important parts of the value of a mattress purchase in post #13 here that can help you make more meaningful comparisons to other mattresses or any other “finalists” you are considering.
I don’t see a “Temerax” on their site but if you mean their Tamarack mattress then if you can provide the specifics of the materials inside the mattress (see this article) I’d certainly be happy to make some comments about the quality of the materials inside it or the mattress as a whole but as far as I know none of their mattresses have any lower quality materials or weak links in their design. A forum search on Rocky Mountain Tamarack (you can just click the link) will also bring up some additional comments and feedback as well.
Phoenix