Ok I found what I knew was out there so I will just copy it here.
To help explain my last post
It is all about the money. Hydro is cheaper!!
Now many will dispute that but if you are doing this as a hobby get a belt.
If you are doing this for a living than the only option you have is hydro.
A mower does not cost money. A mower makes money.
A mowers price is so small compared to the income it will generate that price is a non issue.
What is an issue is time. Time is all you have to sell. There are a lot of things you can do in business to adjust the level of success but the one thing no one can change is the amount of minutes in a day. So you have to pull the most amount of production out of each minute as possible. The best way to do this with a W/B is by having a hydro.
If all you do is mow wide open fields than it would be best to have a Z but for smaller lots with obstacles you need maneuverability and that means hydro.
Most belts are very bad at backing up and you will do a lot of pulling. And forget trying to back up a hill , which may be a lot in TN. And even if it does go back a little you still have to stop and switch gears to do it where a hydro is instant back and forth.
A hydro will be more productive and less tiring and therefore will cost less for you to own.
Also if a hydro is jerky, it is because the operator has not learned how to operate that mower yet.
My first mower was a belt, and it is a good mower but I learned fast that I needed a hydro. All new W/Bs have been hydro. Because we do this to make money.
The main reason I bought a belt was I had not yet found this site where people could set me straight.
This was written for a guy in TN so you may not have the hill problem