It's only been a few months (for the roof). They still work exactly as they did out of the box. Don't plan on ever buying any other brand as they seem to have a lifetime product quality which is rare these days. Highly recommended.
These are the nicest scissors I have used and I have used all manufacturers. The scissors are sharp and don't have the jagged edges that some scissors have (making the cut cleaner). The cutting blades are longer than some other scissors, so you'll need to open the knife wider to take advantage of this. (helps to have big hands) I LIKE BOB
The klenk brand aircraft shears (aka metal shears) are the tool you need, especially when wearing large or very large gloves. Your bread and butter is your scissors. This particular knife has a wire cutter feature that is great for use with flexible wiring.