Yeah Denny Jones is in Cambridge his family actually started the cambridge branch.It use to be Jones implment before it was atlantic.
Service seems to be a common problem with walker.I think its actually a walker thing to not a dealer thing. From my understanding they are very hard to deal with from the dealers side of things.The near about break you before you ever get started. To become a dealer you have to buy like 10 units and when they arrive must be paid in full. There is also next to no mark up on parts and i belive that the dealer has to stock a certain amount of them. I really don't know why any dealer would want to carry them exept for the fact they are a good product. The big dealer probbally dont want to tie up that much money and room for a product that isnt going to sell like a normally ztr.
Not to discouage you from a walker, but depending on what your looking to do with it a ztr with bagger may be a better suit for you. I know you said you do a lot of different types of yards and i can tell you that on the crappy one's the ztr with bagger will be better. If your intenions are just to use it on the good ones i'd go walker.