I now have 26 hrs on my new SuperZ 28/60 with the XR-7 deck and FUSION blades. I wanted to see how long these blades lasted prior to sharpening. For those who know me, I'm a blade freak. Always sharpening, always tweaking and fiddling around with things. At 5hrs I was changing the oil and took a look at their condition. They were great and sharp as can be. Same at 10, 15, and 20hrs. I decided to remove them tonite and touch them up and balance them. They definately NEEDED to be balanced. Two were off by quite a bit, and I'm sure that will take out that slight vibration I've had since new. Anyway,....no major nicks or gouges in the blades at all. And I have hit a few things with them. With being a new mower, it took a little learning curve to get a feel for "floating" the deck around and over things. Here is a picture of the condition of the deck after 26 hrs. It has not been scraped yet since I bought it. Not bad for a week plus of mowing.