Purchased this mattress for my 2yo son's full-sized platform bed - was excellent! Coupled with a gel-memory foam topper, is extremely comfy & moderately soft; my sis has a tempurpedic mattress & says this mattress feels the same! My son sleeps so well; no squeaky noises when I get onto/off the mattress or when my son turns in his sleep. I often sleep on the same bed with my son, and feel the mattress offers excellent support (maybe b/c of springs...I don't sink into the mattress). Did have a slight odor on arrival...was gone after 48hrs. Would buy this again. Can't speak for durability though as I've only had it for 1 month; however, it does seem like it'll last - probably longer than a regular memory foam mattress.
Update - 4 yrs later, mattress so great, I purchased a 2nd for my daughter's platform bed. Absolutely no complaints. I slept on the first one with my son (for 7-8mos...through pregnancy), and had no back pain. 4-y-o mattress still looks great, no sagging. My kids sleep soundly every night, so I have no reason to complain =)