I'm so in love with this stuff!!
we got a new regular mattress about 2 years ago, nice and firm, but since i've lost a ton of weight i don't have a nice 3 inch cushion of fat to soften the pressure on my hip joints LOL at least that's what i tell myself!
so i bought a 3" memory foam topper for the bed @ Costco, what a treat! it's weird at first, but them you're cradled in comfy-ness and no joint pains for a while now