CMT makes great beats. But it has some inherent problems. The board to be cut, standing upright on the router table rail, has a fairly jagged edge that tends to leave some gaps along the seam when the second board is cut (cut along the table). Be prepared to use lots of clamps - I mean LOTS to try and make a seamless connection. I don't think it's the beat or the quality of CMT. It seems to me that this is the nature of this type of beat. This is the first time I've used the miter lock bit, so it might just be recent user error.