My Gravely 34Z has around 40 hours on it so far and I am happy with it. I have found that the mower really takes a beating going over rough lawns and squeezing through tiny gates and spaces. How durable are these things? For instance the other day I was mowing an unfamiliar lawn and I did not see the rut and both of my front wheels went down into it and almost made me completly stop. I was worried that I may have bent the front castors. I have also hit the deck on some things even though I try to be careful. Do I have anything to worry about? How easy do spindles, decks/deck arms, and frames bend? what things should I be careful of and try to avoid? Also, any maintenance tips will help me out too. The book say to grease/lubricate pivot points every 50 hours, but there are very few grease zerks.