I bought a 9" latex mattress with 3 layers earlier this year. I find it more comfortable without the cotton/wool quilted cover, so I unzipped and removed the top of the mattress cover and I just have a mattress protector over the mattress. I’ve left the quilted cover on the bottom and sides. The slides slouch down but it’s not the end of the world.
I will be swapping the current mattress protector for a stretch waterproof protector and new stretch sheets. Do I need a new mattress cover that covers all 6 sides? I could get a stretch cover, and I guess I like the idea of an additional layer of protection, but do I need it for any reason?