Hi doshspy,
They changed the design of the Pure Echo and it now uses more costly materials and components which is the reason for the difference in price.
There is a great deal of information in post #2 here and the topics it links to about mattresses and children and “suitable” and “safe” materials including a link to some general guidelines for children in post #2 here. It also includes a number of links to the better forum posts and topics about mattress and children as well which have more information about many good options which would be well worth considering.
Phoenix