We are in the process of shopping for a double size mattress as we will soon convert our three year olds toddler bed to a full size bed. We purchased the Naturepedic crib mattress for him as that was important for me for no dangerous chemicals in his mattress. I was planning to purchase the Naturepedic quilted mattress in double size but first wanted to look into the comfort of this mattress as I would like it to last him until 18 years old. Does anyone have a 'non-crib' Naturepedic mattress and could offer your opinions on this mattress? And also did you use the Naturepedic foundation as well or another brand (not sure if foundations contain dangerous chemicals like mattresses can)? Also, please let me know if there is another 'safe' mattress that you would recommend as well.