A little late to the party, Matt, but I have a John Deere zero turn with a 60" deck. It does a great job. There are some design issues that they may have solved/changed by now (mine is 8 years old), but other than that, I love it. It would be very hard to go back to a riding mower. The advantage to a riding mower is that you can pull a cart and such. But I have an ATV, so I don't need that feature...
I mow about 2 acres (around the house, the driveway, and around the exterior of our pastures...two swipes). Does a great job. I used to mow our three 3 acre pastures with it. But the tallest I can set it is 5" and needed higher so I got a finish mower for my tractor for that. But even so, when I was mowing the fields, I could do a 3 acre pasture in about 1 1/2 hours. Cutting wet grass? Well, yeah, you "can", but wet grass clumps up. So, I don't do it...