I love this thing! Before that I cut the tongues with a straight cutter and a ruler. I will never return. This bit reduced the time to complete this task by at least 80%. The beat cuts great too! I used it in birch plywood and 2x4 douglas fir. Cuts smoothly and cleanly with no sign of slowing down. With my 2 1/4 hp router I can route full depth in 2 passes with tongue and groove. Damn it's cold, probably in one go. Overall a great beat! Highly recommended!