Truly great jig. I hung 8 French doors for a family member this past weekend. This tool made very quick and precise mortises. I used the 5/8" radius for the rounded hinges that were chosen for this project and in a word, perfect. I didn't try the square hinge part of the tool as there was no applicatoin for that this time, however, after mortising in 24 hinges (3 per door), the jig worked like a champ. The router bit provided in the kit did the trick. I didn't need my chisels at all. Highly recommended.