I made 1,000 mini cupcakes a week ago for a charity food festival. I used mostly my real heavy duty commercial pans, but needed more so I bought 8 of the Wilton mini pans to make sure I had enough. I knew exactly which pans were used for which flavor. The ones made in the Wilton pans had the liners peel away. This did not happen on any of the heavy duty pans. I believe it is not a matter of underbaking like I used to think, but that the average home pan does not get hot enough to properly bake the cupcakes, even though they are baked til done.
If you want to prevent peeling, buy the heaviest pans you can get. Stay way from dark pans. Gravitate to dullish shiny pans rather the very shiny pans. I no longer have a problem since I stopped using the flimsy, cheap and dark Wilton pans. There is something about how hot the baking pan gets that helps seal the liners to the cupcake. And a lightweight thin metal pan cannot get as hot for as long as it needs to properly make sure the cupcake liners adhere.