Leo, right now my mattress is made up of HR foam and a sensus topper. With 4" of Sensus it's too soft and with 2" of sensus it's too hard. I am thinking of buying a 1" Sensus topper so I can try 3" which might be "just right". Or maybe 2" of Sensus and 1" of Venus??
With my shoulder/neck/back problems I am always searching for something that will give me just a little better night of sleep. My usual pattern is to sleep maybe 4 good hours and then struggle, tossing and turning, the remaining 3-5 hours due to back or shoulder pain. So it is kind of like searching for the lost ark, and I'm always tweaking my mattress to see if I can do a little better.
I would like to try a different core instead of the HR foam, so I am thinking of Dunlop latex and/or Omalon. Or a combination thereof.
What's weird is that with memory foam I always love the first few nights and then it softens up too much and I get lower back pain. I thought maybe the Sensus was firm and dense enough for this not to happen but it did. Then there is the question someone mentioned: Is this overstock.com Sensus really Sensus, or is it perhaps a bootleg version? I'm not sure since I've never seen or tried real Sensus.
I will say, however, that the 5" of M-Grade Foam was the best I have done in the past couple of years. I think maybe if I'd bought the 7" core of M-Grade foam by itself instead of the 5" M-Grade with 2" of memory foam glued to it, I might have found the perfect mattress. If my experiments as outlined above don't work out, I may go back to overnightmatress.com and buy that 7" very M-Grade foam for a core and then add some Sensus and/or Venus memory foam on top and/or Dunlop on top.