I have both but prefer the sheets I bought on-line a couple of years ago. The pad of FP I bought at a quilt shop (Jenkins?) was thrown in the trash. Once it was ironed on I couldn't get it off. Sometimes my local groceries don't carry the Reynolds FP so I bought a box of FP sheets from a restaurant supply place.
won't ever have to buy any more...box contained 43lbs of paper! Love it though.