I have an 04 Prius with 117000 miles on it. In the earlier years I had all the problems with the car stalling or not wanting to keep going, but Toyota finally resolved those issues with software upgrades and recalls. For the past 3 years I've had no problems. At 112000 miles I needed a new water pump, but otherwise I've had no mechanical issues. The battery is fine. I drive exclusively on local roads, 40 miles each way to work, and get 48 mpg during the winter (New Hampshire winters are brutal) and am now getting 57 mpg in the Springtime. The car gets significantly less gas mileage if I only use it for short hops (5-10 miles) or if I drive on the highway.