Planning to move K to a big kid bed (full size) a couple months before baby number 2 arrives and needs the crib. Looking into the mattresses and box spring and trying to figure out which to go with. For the crib, we splurged on a Naturepedic and have been happy with it, but the price on the full size mattress has me in sticker shock.

Any suggestions, links, tips on mattresses for big kid bed? Affordable organic would be a big plus. Obviously, we hope she'll use it for a long time, so I don't totally want to cheap out on it, but overwhelmed by all the choices. Thanks!