It was MUCH firmer than a medium, as in it doesn’t give at all when you first get on it, but the foam top gives once you are on it for a couple minutes.  It sort of forms to your body and position this does make it comfortable as long as you don’t move.  If you move, it takes a while for the part that formed to you to pop back up, so there’s an indention there for a while and you can roll back into or towards it.  
I’ve had it for a month now and I’m a little suspicious  concerned because there is already some “bunching” of the top, foam part of the mattress.  See photos. 
Lastly, it definitely sleeps hotter than my previous coil mattress, and I will be hunting for a cooling topper. 
I’ll give it another month and re-evaluate on the bunching of the foam and fabric at the top of the mattress.