Twice bad experience with the same problem

In 2009 and 2011 I put me for a respective 4.3 inch and 5 inch Navigon to a protective bag. In both instances after a relatively short period of use, the pull tabs of the zipper was broken. The 4.3-inch pocket have provided means of 2-component adhesive with a spare.
The same problem arose after a short time in the 5 inch pocket. After I had damaged fingernails when pulling, I sent back the bag.
In specialist shops, I've bought a protective bag from Garmin. This has a Velcro closure instead of the zipper. With this version I am very satisfied.
Of the Navigon mounts I want customers who want to save trouble advise.