I found a queen-sized 4" perforated memory/gel foam topper that has worked fairly well for my wife and I who are both side sleepers. It can still get a tad warm in the summer months but not unbearable and it doesn't turn into a rock in the winter (it does firm up a bit until your body heat loosens it up). We use it on top of the base mattress in our Autana so there is still support keeping us from bottoming out. Using only the topper we still would frequently wake up with sore hips and shoulders like we did with the mattress pad. I haven't had any issues leaving it in the tent.I think it's to firm and kills my back when it try to sleep. I've tried a couple of foam toppers for beds but find it still to hard. Trying search out a solution.