Avenco 10 Inch Full Hybrid Mattress

I bought this to replace a mattress that was over a decade old and had a bad sag on one side - causing unacceptable levels of lower back pain. The Twin XL model failed to appear after it said "delivered" however, so I got my money back from Amazon and tried to re-order the same model, but the price went up thirty or forty dollars in the interim weeks, forcing me to opt for the cheaper Twin (just Twin, not XL) "for kids". I got what I paid for. It arrived on schedule and inflated rapidly enough that I was able to sleep on it the first night. While not uncomfortable, it started out a too firm for my liking - so hard I couldn't sleep - so I added a 3-inch layer of foam overlay that I'd gotten for my previous bed. Sank right in. SUPER comfortable after adding the foam. Going to sleep on this bed was NOT a problem after that. But... after a couple of days I started waking up with increasing levels of back pain to the point where it finally took an effort just to roll out of bed, and about 30 minutes before I could sit or walk without pain. I thought I may have added too much foam, so I switched to a 1-inch foam layer and tried to sleep without foam for several nights after the bed softened up a bit. Same problem persisted regardless of foam, though. After 30 days, I could see that the Avenco mattress started out firm but quickly sagged in the center. In fact, it got too soft over a short period of time, and the problem was that it couldn't support my weight in the center of the mattress. It was never a problem laying down and going to sleep - the foam always absorbed me and sent me right to dreamland; SUPER nice way to go to bed - but I'd ALWAYS wake up in pain (more than I had on my previous old bed). I tried to sleep on the firmer edges but invariably ended up in the middle with a LOT of pain in the mornings; enough to make walking difficult. I'm 49 years old, 5' 11'' and around 220lbs. Most of my weight is in the center. I think for a smaller person this would be a perfectly adequate mattress, but for me, my weight and body shape, it just wasn't firm enough in the center. Shame too, because it was SUPER comfortable to lay down on every night, but just horrible by morning. I've opted to try a "Luxury Firm" Saatva mattress for about twice the price which should arrive in a week or two, but until then I'm going back to my old mattress. On the brighter side, Amazon customer support was super friendly, and arranged a UPS pick-up within 24 Hrs. plus my money back. Fingers crossed that the extra expense will be worth the hassle in the long run, and I hope this review helps anyone with lower back pain considering buying this mattress! After 30 days, it softened up all right, and it was EASY to fall asleep on every night - especially with an added inch of foam - but to paraphrase William Butler Yeats, "the center could not hold, and severe back pain was loosed upon my world. And what rough bed, its hour come round at last, slouches towards my house to be born?" Update: For those curious, I wasn't able to return the mattress after it was opened and expanded. UPS wouldn't take it unless it was either in the original container or packaged and ready to ship (and I didn't know where to find a mattress-shaped box, etc.). After being bumped around on the Amazon Customer Support line for a while I finally spoke to someone who gave a full refund and said that since it was opened and used for 30 days they couldn't return it and/or it wasn't worth the hassle of shipping. So, they gave me my money back and suggested that I donate the mattress locally. Lesson learned. My next mattress from Saatva said returns will cost an additional hundred dollars, but if I have to use that option, I think of it as being cheaper than doctor's bills, lol. Thank you Amazon for your great customer service reps! Update #2: After refunding my money and telling me to just donate the mattress, I got an email saying they would bill my credit card for the full amount if I didn't send the mattress back in x number of days. I don't use it - I don't care if someone takes it - but what a hassle! Amazon assured me that UPS has a "compressed package service" that will deal with the expanded item and compress it back down, but my local UPS store has no idea what I'm talking about. Now I have to get back on Amazon and deal with people putting me on hold and transferring me around for another 45 minutes or get re-charged. I think I might give a lawyer friend a call first, lol.