First of all, I'd like to say you have a great machine:260z. This thing is a workhorse. I demoed many machines and did lots of research. While most of the ones I demoed were relatively the same, the gravely was an exceptional value. I just have a few questions you should be able to answer. First of all, before on my old Z, I sharpened blades every 8 hours. The gravely came with tungsten carbide coated blades I believe. How should these be sharpened? Also, I'm interested in perhaps trying doubles. Has this ever been done succesfully and would it void my commercial warranty? I thought I read somewhere you manufactured a kit... Next, how much should I expect to pay for the striping kit (rubber flaps) on the back of the deck. E-mail me a price if you'd like... Also, if I attach my own kit, it won't void the warranty, correct? Lastly, how do I go about putting a rear hitch on this mower; do you guys make one?