Needed a window fixed that the hardware was out-of-whack on and would not open or close properly. Called up Networx explained to them that I had not hired them but the previous owner of my home had the windows installed by them and I thought they'd be the best people to call to fix it. They were here within 24 hours, fixed the window, and free of any charge. They were efficient and friendly.
Now, I'd say that is a company that stands behind their product. Most businesses will not honour that unless you were the original purchaser.