I bought an inexpensive memory foam mattress from Overstock.com long before I was diagnosed with RA. Best purchase I've ever made. I, too, was concerned it would make me sweaty, but it has never done so; same temp as traditional mattress.

I couldn't do pillow top anymore. Not enough support. Too many pressure points with regular mattress. My body hurt more when i woke up 4 to 5 times a night. We bought a temperpedic. Love it. I get back to sleep faster after waking up. It was expensive but it will outlast any regular mattress and it helps my body more.

I'm a true believer in my cushion top. Don't like all those fancy ones. I have a pillow with a "cooling pad" which helps, although I still get up and my hair is dripping wet. Night sweats SUCK.

You can always get one of the mattress toppers that are temperpedic. They have them at Sam's, Wal-mart and other places. They come in different thicknesses and are considerably less money. We have one on our bed that is 3" thick and it's made a big difference for me.

We have bought two tempurpedic mattresses of them. We had a queen but recently got a king size. Yes they are expensive but so comfortable. We financed 0% interest for 6 years for our bed, mattress and foundations. I don't think we will ever own another brand!