Very comfortable! Probably the best mattress I have ever owned. I am a back and stomach sleeper so this mattress works perfectly! Only one issue I have and it’s a really minor issue, is the sides should be built stronger like the middle of the mattress. Sides will collapse about 3/4 of the way when you sit on the mattress and if you sleep near the edge it will collapse 1/2 down, leaving you sleeping at an angle to you side. You have to sleep about 6” to 12” in from the edge so you maintain level when sleeping.