My timing chain was less than 2 years old and stretched way out. I've heard lots bad about gear drives, but of the few I've owned never had any problems. As with any aftermarket parts, good installation is critical to good operation. I've had a couple PJ's and they work great. I had a Milodon on a 440 Dodge and it was more af an HP unit that required some drilling and tapping into the block to mount the idler. If you want perfect cam timing and don't mind some noise and expense it's a good way to go.