This was a nice upgrade to my planer. Shortly after sharpening my blades about a year ago, I nicked them again. After seeing a couple of reviews on spiral cutter heads I decided to upgrade basically from the sheer ease of rotating one of the carbide inserts to repair a chip. Excellent instructions are included but be prepared to spend more time than the 3 hours stated. I had a problem removing the bearing on the gear box side of the shaft. It was a real pain but I was finally able to get it to release. Grizzly customer support was excellent, they recommended replacing the bearings, seals and gearbox gasket... and that was a good decision since I ruined the one bearing when removing it and I don't EVER want to open this machine up again because of an oil leak or noisy bearing. The cut is great and the chips that are produced make it easier for my dust collector to remove them (another big plus for this upgrade). I was so sick of the chips clogging the outlet... this upgrade will be worth it for that reason alone!!!!!