Wessman,

I can only agree with Bill Robinson, JAKA, and I2DDD,
I have been using the METRIC Fox reamer, which has a 1/4" first step, that grows to 7mm and then to 8mm.

I have reamed APC, Bolly and Master Airscrew fiber filled props and many wood props.
I also did a few carbon fiber props, on the 8mm size.

The tool remains sharp and easy to work with. A little dexterity has so far prevented my knuckles, from being "mutilated" by sharp trailing edges.

I don't know if the GP tool is a POS. But if saving $1 is economy, what can I say?