Our first sleep science bed purchased from South Bay International, Inc. in Pomona Ca (through Costco online) came right out of the shrink wrap smelling like mold. We returned it and received another. My husband just found that the entire underneath side of our bed which we have been sleeping in for over a year (with our 2 year daughter), is COVERED in MOLD. Our daughter wheezes at night and I have been fighting a sinus infection for over a month, which won't go away even with antibiotics. There is no other mold in our home and nothing was EVER spilled on the bed. Both Costco and the manufacturer, South Bay International, Inc. are refusing to acknowledge they are continuing to sell a faulty dangerous product. BEWARE.

We purchased the queen size Costco Sleep Science 10" Natural Latex Mattress in July of 2010. The delivery team was wonderful; they placed the mattress on the foundation, moved it to our specifications, and removed all of the packaging.

After reading several reviews, we chose NOT to buy the Sleep Science foundation. We ordered an oak platform bed from Platformbeds.com.

This mattress appears very well made. For the first week or so, it seemed a bit too firm, although we slept quite well, with no back pain whatsoever. (Our old bed was a softside waterbed with a memory foam topper, so any bed would have probably felt hard!) We are presently using this mattress with a 1" talalay topper and a wool mattress topper. Even without the toppers, this mattress sleeps much, much cooler than the waterbed with memory foam topper.

We have now had the mattress for four months and are very happy with this purchase.

Our two Costco Sleep Science beds were delivered on Saturday morning! Here's my review:

First, about the delivery. I found the delivery company to be professional and friendly. They called to schedule the delivery, called again when they were on their way and arrived on time (a little early even). They assembled the foundations on my front lawn and seemed to know what they were doing; they were quick and efficient. They set up the beds in the order I requested and exactly as I instructed. I have absolutely no complaints.

Second, the foundations. They are made of metal tubing, with plastic top panels to support the mattress and then all covered with a cloth cover. They seem very sturdy and since these two beds are for my kids, I have no doubt they will be more than adequate. The cover has tan sueded material around the edges to match the lower part of the mattress cover and together they look nicely matched.

Third, the mattresses. I can't imagine how anyone would describe them as too hard or firm. They are too soft for my husband and I (we are larger people), but should be fine for our kids. I do find them comfortable for brief lounging and snuggling with the kids, but just about bottom out at the edge when sitting to get in or out of the bed (for reference, I am 5'-7" and 240 lbs). I haven't slept in one all night yet, but my husband did and said it was too soft, but still better than our awfull inner-spring that we are about to replace. He had some minor back pain upon moving around the next morning. The cover is nice thought nothing spectacular. The upper portion is white cotton material, the lower is tan sueded material. I haven't opened them up, so can't comment on the interior. They were delivered already inside the mattress cover and rolled up in a plastic casing. The delivery men cut open the casing right on top of the foundation. They said it would take about 2 hours for it to fully decompress, but I didn't notice much of a difference 2 hours later. The mattresses definitely have a latex smell. I've heard others describe it as sweet or cookie dough-ish, but I didn't not find it that pleasant. It also wasn't a foul odor, just noticeable. Once they had been sitting a while and had the Luna mattress pads and sheets on them it was only detectable by putting your nose right into the mattress. I found they smell almost exactly like the JC Penney latex pillows I recently purchased, so I don't think their smell was unusual or indicitive of a quality issue.

Overall, I think was a good buy (for smaller people, or those who like soft beds). These are our first latex mattresses and I love the substance and weight of them. So much nicer than the bouncy-ness of an inner-spring mattress.

Edited to Add: We will be returning the foundations that we purchased along with these mattresses. They are shoddily constructed and are already falling apart. We are still happy with the mattresses themselves, just not the foundations!