I dislike the Printfile plastic storage materials - my negs always seem to stick in them, and I'm uncomfortable with pulling on the negs until they unstick. And yes, before you ask, the negs are dry before they go in

I now use glassine envelopes for my 4x5 negs, and glassine sleeves for my 645 negs. Sure, you can't contact print the negs through them, and it's difficult to see the negs without removing them from the sleeves, but overall I find them easier to work with.