My buddy has had one for a couple years now and I took it for a test drive last month. He swears by it and I must say I was impressed. I was looking at the "scheduler" model that can be programmed to come out whenever you want. They are pretty fun to watch for a bit, especially when they automatically go back to thier charging base.
Rich, I agree, as cool as they are, you are asking for trouble getting it for your wife!