Upon first examination it feels extremely firm and some would say it's hard but the construction of This mattress defies easy characterization.  After one month of use it holds it's form and structural integrity around the edges better than anything I've tried.  Upon delivery I thought it would be too hard to sleep on but after 4 weeks I have found that I get a complete 7-8 hours of sleep before waking.  Back and shoulder kinks and pains have gone away.  I don't know if my body is telling me something, but seems like we'll keep this one.  And...for whatever reason, the cats prefer this mattress over all the others in the house.