I have been using the BACtrack S80 for years. I have had one in the car, my truck, my Harley and my wife's car for years. Use one each time before driving to avoid driving over intoxicated. It's way cheaper than the alternative of driving under the influence and getting cited or killing someone. I recently bought th C6 and have loved the smaller size as well as the quicker reading time than the S80. I ended up buying 2 more to have in our main vehicles. It so much smaller and can fit in my pocket like a key fob. That means I can take it into the bar in my pocket or my wife's small purse without having to go out to the car to test my BAC. I would highly recommend the C6 and still need one more to put in my Harley.