I am just finishing my first roll of the Pellon polyester batting you are asking about. I got it at a Joann's sale several months ago and plan to pick one up next Saturday when the same sale is run again.
It is not like Warm and Natural at all, but I like this batting. It is much more lightweight than W & N and much thinner. It has been easy to work with for me. I used two layers of it for a quilt made for a nephew who lives in Minnesota in order to get more warmth.
Our Joann's store is not one of the big ones, so I will need to get to the store first thing -- last time they had gotten only 3 rolls in for the sale, and they don't carry it regularly (at least not in our store).