Years ago I had a couple of augers retrofitted with Pengo teeth, and simply couldn't believe the difference. The way it is set up, no two teeth travel in the same path, so when the first tooth skips over a fist size or larger rock, the following tooth (or teeth) which is offset from the first, will probably snick the rock right out instead of the auger bouncing around in the hole.
Also the auger simply digs better because the cutting is done with much smaller "edges". Kind of like loosening the compacted soil with a pick versus a shovel. This especially helpful as most 3PH's do not have down pressure, so gravity and the auger configuration are your only friends.
If you are digging in an area with a lot of glacial till loaded with "alley apples", you should be very pleased with the performance, especially compared to traditional bits with plain cutting edges.
Great find!
Ron