Well I've used it about a dozen times and I'm completely satisfied. Four stars instead of five because the end that attaches to the valve stem seems a little flimsy and I expect it to fail/stop working over time. Luckily, the tube from the grip to the tire is interchangeable. OTHERWISE it is very easy to use. 5 stars for the price. For a professional auto repair shop, I would recommend an all-metal body with no digital display.