Hi Vicky,
I would be cautious with a 2" layer of 1 lb polyfoam in the quilting which is a little outside the guidelines I would suggest (even for a two sided mattress) and could be a potential weak link in the mattress.
While it would be more durable than many one sided mattresses in the mainstream industry … in terms of the quality and durability of the materials and the useful life of the mattress I think you have better options available to you.
Phoenix