I'm a newbe and looking for a good ZTR. Maybe I'm ignorant but isn't it the distance between your wheels instead of deck size that determines how fast you mow? Since you ride in the same tire track, it doesn't matter how wide the deck is, only how wide the wheel base is. Am I wrong? I'm trying to decide if I should get a 60" or a 66" mower but since the wheel are the same distance apart, won't they both cut at the same rate??? Thanks for your advice.