Bag still zipping after 9 months of everyday use!

We took a passenger train trip in October 2011. Being that we had limited space in our suitcase, I put my essential make-up products in a Ziploc Quart Size bag. When we got home, I put my Ziploc of make-up in my regular make-up case, making it easy to find my everyday essentials. It is now June 2012, and this little bag is still in use and the zip still works perfectly after 9 months of everyday use !!!!! The bag isn't shiny anymore but there are no holes in it. This speaks volumes for what a wonderful durable product Ziploc has. I am amazed !