Zinus Full Size 13.5" Cooling Foam Mattress

TLDR: I'm really surprised how much we like this mattress. Two thumbs up! I highly recommend it as long as you aren't concerned with non-padded sides. We were moving our child from a toddler bed to their first real bed. The toddler bed was essentially a bed frame with a particleboard base and the Moonlight Slumber Little Dreamer foam mattress. First, we started with this bed frame: https://www.amazon.com/dp/B078HZYSG8?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_5. Then I went to the big box hardware store and got a 1/8" piece of plywood to serve as a mattress base. After extensive (ie 10 hours) online searching for a mattress, I decided to go with a 'mattress in a box' instead of a traditional mattress for many reasons. I zeroed in on this Zinus 12" with pocket coils and cooling foam for a few reasons: - Zinus is a known newer brand with a reputation they need to maintain - Sold and shipped by Amazon with the 100-night Amazon return policy backed by the 10-year Zinus warranty - Foam over individually pocketed coils, which we thought would provide the comfort of springs with the foam my child was used to (we bought a much more expensive 'top of the line' solid foam Tuft and Needle cooling mattress for our other child, and honestly after 4 years? meh. Heavy, which makes it hard to change the sheets and worse, it sleeps super hot) - Fiberglass free and claims that they don't use harmful chemicals, OEKO-TEX standards, etc. (I mean, why not if you have a choice?) - Medium firm (similar to the toddler mattress my child liked so much) - Cooling gel (my child is a hot sleeper) - Low price (if my child hates it? Oh well cheap experiment). We bought this in February 2025 and delivery and set up were easy enough. I unfurled the bed in an empty room and within 30 minutes, it was useable, but we left it alone for 5 days. Ever so slight chemical odor that went away after a couple days. My first impressions were that when I moved it, it was light and felt cheap. There are no sides to a 'mattress in a box' and you can feel the springs when you touch the sides. 'Oh well' I thought and proceeded to put it on my child's bed. Seemed really comfortable once you hopped on and were in 'sleeping position'. Easily supports my ~170lbs so it is definitely supportive of my child, who was thrilled with the new bed. Being able to really feel the springs on the side bothered me, but if my kid's happy, that's all that matters. Fast forward 5 months (July 2025) and I couldn't be more pleased with the purchase. My child used to wake up ~1am every single night on the old toddler bed and wander into my room. That has only happened 2x in 5 months. My child thinks it's a super comfortable bed. I do as well. I often lay in that bed until my child dozes off. I have messed up shoulders and always experience pain when laying on my sides in my own bed (super fancy Sleep Number with an adjustable base and the remote controls). I'm also a very hot sleeper and in the summer, I will sweat in the Sleep Number. Admittedly, I myself often doze off in this Zinus bed on my side for a couple hours while putting my child to sleep and wake up with no shoulder pain - and I don't wake up sweaty at all. There are no indentations on the bed after 5 months. All that said, I'm super impressed. It's not a premium feeling mattress, but it gets the most important part done - providing a really comfortable surface to get a restful nights sleep. Once my Sleep Number breaks, I'm going to explore Zinus's 'lux' options at that point for my own bed (perhaps a deep Zinus pocket coil spring and cooling foam on top - and put that on the Sleep Number adjustable platform). I'll come back and update if the springs or memory foam start breaking down, it starts sagging/retaining body impressions, has springs coming out the size, etc.