Problem With 2x2 Carboard Holders

I keep a large portion of my collection in 2x2 carboard holders and stored in the 20 pocket binder pages. Never used to be much of a problem until recently. Perhaps it is the quality of the 2x2's these days. I find that they work well for thinner coins up to quarter size but when you get to thicker coins like halves and dollars, the mylar film often separates when stapling them closed. For this reason I use the large dollar size for my halves and large dollars are usually placed in flips. I find it better to use and oversized denomination 2x2 rather than the specified size for many coins.