I have owned a Gravely 260Z with a 61 inch deck for four+ seasons now.
I am very happy with it.
I have a regular full time job and I currently mow 12 lawns, so I have not exactly put it through its paces like someone who mows full time would. Right now, it has about 480 hours on it.
At first, I was a bit hesitant on the idea of a hydraulic lift deck. The gravely also has a swivel front end much like a tractor. My theory is, the more moving parts you have, the more things have a tendency to break. This is not the case with the Gravely.
I am knocking on wood right now! I also like the way it cuts and stripes lawns and so do my customers! I guess that is the true test... right!
The bottom line... the 260Z has been very dependable for me and if I get another ZTR it will probably be a Gravely.
I also know someone who runs Toro's and he says he has had very few problems with his mowers as well. He mows full time and puts about 40 hours per week on his ZTR's.
If I were you, I would demo as many mowers as I could so you will be happy with what you eventually get. These mowers are way to expensive to later find out you would have been happier with something else.