It's great on serrated edges. You just use the angle side (edge) of the stones - it couldn't be easier and brings them to very fine edge. You can't re-bevel an edge with the Sharpmaker, though, at least not without using wet/dry paper against the rods.

I've had mine for about a year now and I've broken one of my medium rods. It fell from a desktop and broke into 3 pieces. I epoxied it back together, but I still can't use it as a normal rod because of the tiny cracks where I glued it together.

One thing I haven't tried are the ultra-fine diamond rods. I'd like to hear how those work out.