If you look on the website, you'll see it can give you a ton of data on your vehicle...fuel mileage, sensor readings, etc. Some it won't be useful unless you're a gearhead or are looking for specific area data when considering some kind of upgrade to you truck...for me, I'm looking at it mainly for the trip computer, but I'm interested in the other things it can do. For this reason, I'm going to wait until I can find it for cheap used on ebay. I have a GPS too, but other than the actual MPH, it can't do anything this unit can do.