Some tools, yes, I will buy the expensive ones. Sorry, but a compression tester is just not one of them. For how little they are honestly used I can't justify the price of some of the "fancy" brand-name ones. If I am really all that worried about it i will go down and use the calibration equipment we use for calibrating gauges at work. Until then, I'm going to stick with my cheap-o autozone tester that reads the same fucking thing as your fancy-ass one, for probably less than half the price.