I've had use of a Grasshopper for a couple of summers and it is awesome. The zero turn is FUN but the machine itself is very practical for mowing large areas--it gets the job done fast. It's not much good in my yard though, because there are trees and flower beds & such--the mower will go around things easily, but the front yard is small & just not a lot of room there for a big mower. In a bigger yard with more room it's great for mowing around trees and such.
As a side note I'll add that a friend's husband made himself a bigger mower--not a zero turn obviously, but since he made it for mowing a large open area he didn't need the zero turn feature. He took his riding lawn mower and attached an 'arm' with two more mower blades attached and fixed up a belt to run the two extra blades, and he's got a machine that will mow his big lot in 1/3 the time it would take with the standard riding mower. He's got the mowing power of the Grasshopper for a fraction of the cost!