My 2 year old son is sleeping on a Colgate I in his toddler bed currently, but we'd like to put the mattress back in the crib for my 3 month old, and buy a new mattress for the toddler.

Can you recommend a cheap and comfy mattress for him?

The organic ones are too expensive. I don't mind a coil one since it's easier to change the sheets on the toddler bed than the crib (LOVE the foam mattress in the crib for this reason!), but I still want a good quality one. Thanks!