Originally Posted by Ridin' Green
I am not sure why most homeowners want to know at warp speed. It isn't necessary, nor does it produce the best job. Plus, it's harder on equipment by far. That said, I would look long and hard at the GT. It will pull much heavier loads than any Z will, and it will be far more versatile for the average homeowner in the long run unless you never plan on any gardening, lawn rolling, snow removal etc. If you never plan on mowing for a living, you won't miss the Z. Most guys don't mow at full sticks with their Z's either. Either the ground is too rough, or the property won't allow it, so the Z's only real advantages IMO are it's better maneuverability and higher blade tip speed when you are able to go at higher speed across the turf. Unless you use the Z all the time, you will have a lot more issues with tearing turf on turns etc., too.
I own lots of JD equipment including a GT, Z950 and a CUT. I have lots of mowing experience on all three of them too, and for what you are wanting to do I say go with the GT.
I agree, speed while mowing should not be a factor. Did you know that the best mowing speed is 6.5 MPH. Going too fast will beat you and the mower to death, fast. Go for the tractor, much more versatile, much cheaper.