I would probably give it a 4.5 if I could.  It is a decent mattress for the price.  It is a little “springy” for a hybrid so the whole bed jiggles when you move much more than our previous hybrids.  Went for the 12” this time to fill the sheets better, but we honestly like the feel of the 10.5” and the 11” more.  Overall it is a good buy though.