My experience with the KZ is that is it indeed MASSIVE and removes HUGE quantities of wood when used as a chopper.

It outchopped my huge NMFBM.

It outchopped my heavy CAK from HI by a big margin.

It outchopped my Gransfors Bruks Small Forest Axe.

The only user that I have that can keep up is my Busse AK (I have not used my Waki yet) and I have a lot more control with the KZ. My AK swing placement is much less precise and the blade vibrates a lot so, even though it is an effective chopper, it is definitely not my first choice for chopping. With similar grind angles, the KZ will remove more wood in a short period of time then any other Busse I have used.

The grind angle is thicker than necessary for soft wood but mine was very sharp and gives me a lot of confidence that it won't roll on hard wood under prolonged hard use.

The KZ is a very impressive chunk of INFI. I think that If I were a bit more burly (I'm 6' and 185) the KZ would be a better user for me as the current size is a lot to handle for a guy my size. The NMFBM is about as big as I can comfortably handle in a one handed chopper. An 80% scale 0.20 KZ would be a dream come true for me as I would use it all the time. I have a general preference for thin knives.

Bottom line, the KZ is a specialized knife built for big guys that want to have a massive INFI Khuk.