The tool gets the job done. I work with Toyota engines and specifically the 4AGE series. The tool could have been better designed as the side that comes in contact with the valve tends to mark the valve as it has no seat other than the threads themselves. Like most general purpose tools, they are not ideal for Toyota valves and heads. As a result, they tend to snag on the sides of the aluminum shaft that the valves are inserted into. But that's a minor annoyance and with a little persuasion the tool works perfectly - in the long run I'll probably use my own CNC adapter. This tool is practically indispensable when working with motor heads that deserve 4 stars.