So my trusty F935 is finally at the point where I don't want to put any more money into it and the whole PTO system needs to be replaced. So, I am looking at Gravely, partially because that is the closest dealer to me and I have been working with them on my John Deere and Stihl equipment already. I mow about 5 acres a week, and currently have a 72" deck so I don't want to go smaller than a 60". I think I have it narrowed down to the Pro Turn or the Pro Turn 100. My question is in the field, what are the real differences between the two, and is it worh the extra money to get the 100. Also, along those lines, which engine option is the best?