My dad got this bed for his place and I loved the way it felt--like being enveloped in a cloud yet still having good back support--and always slept like a rock when I visited (I have insomnia tendencies so this was great). I recently moved and needed a mattress so I decided to get my own...and after a month of usage, the mattress is very comfortable and I generally sleep very well in it and my partner really likes it too!
The reason I'm giving it 4/5 instead of 5/5 is because it is not as plush and cloud-like as the one my dad bought, granted he got the 12'' and I (being a student) got the 10" to save money, so that likely factors in a bit. I had assumed the plushness of the top portion of the mattress would be relatively the same despite the 2" height difference, but I am still satisfied with the comfort despite this!