Headstock Spline Routing Jig Tool from eBay, TEMU, etc... REVIEW! How Does it Perform?

Like so many others out there, we've wondered if this tool/fixture/jig was any good and if it would be easier to use than creating our own tool to do the job. So we did a full blow review and used it on a guitar we had to repair. Please hit the thumbs up, scribe, and comment and let us know your thoughts of this review and tool.