Hi All, My baby is about 5 months and so far he has been using graco pack & play (playard) with this mattress. I found this mattress really firm though "Dream On Me 3" Rounded Corner Playard Mattress, White/Brown This product is intended to be use from 6 months and up. Dimensions: 37.5"x25.5"X3". Now we want to shift him to crib with a firm mattress. What might be a good bet - something which is economical and can be used for longer time ?. What is the average crib size ( compared to dimensions above for playard) Thnx Riya