HyperVent Marine

Haven't used HyerVent.........

But when we went FT I chucked the OEM mattress and replaced with a TempurPedic mattress.
Had a condensation issue and being cheap I used an 'egg crate' foam piece between bed plywood platform and mattress.
No more condensation issues

That was back in 2007 and still using it

I don't have any experience with HyperVent....

However, I had a terrible problem with condensation under the mattress... it was bad enough that I threw away the mattress and the bedding. I added a layer of Dri-dek and it's now dry as a bone under there.

Cheers,
-Mark

Been using Hypervent for years. Previously had a lot of condensation under the mattress with the beginning of mildew when camping in cool weather. It solved the problem. Pricey, but worth every penny. Money well spent. -Mark.

I use the Froili system on my boat, which has cured any moisture problem. It acts a bit like a box spring as well, making the matress more comfortable. Not cheaper than the Hypervent though.....

Yes, many people swear by Hypervent. I would have it too, but I am kinda cheap at the moment. I was just yesterday looking at more frugal substitutions. Nothing yet.