I am using this binder to put all of my product manuals in which are contained in mini sheet protectors. Unfortunately the bottom ring does not stay closed so my protectors slide out.
I own two of these in different sizes to use to carry sheet music around to different gigs and jams. They hold up well to the rigors of being pushed into a carry case and protect the sheets that have been gathered over years. The flexibility and durability of the cover is the key in my opinion. More rigid binders haven't faired as well. I'll buy more when the collection grows and would definitely recommend them.