I cant see why it wouldnt work on most any normally easy to split wood, hard or soft.
As to it hurting your wrists, you are supposed to let it slip and pivot in your hands, they say that on their site or video I think. Looked at this thing before and the inventor is an AS member.
Id like to try one, but again, there are a variety of $150 to $300 and probably up axes out there I cant afford to just try out. fiskars for 50 and under was tons better than a normal 30 buck generic maul for me. night and day. Goes by money versus productivity, are any of these 4 times or six times as productive as a fiskars? Any of thos high end axes? Even just twice?
I have yet to see actual proof of that. Anecdotals, yes, proof, nope. And it is hard to prove this over the internet, you have to grab one and try it out one afternoon in your own wood, so there ya go.
His design is obviously cool and well thought out. Cut his price in half, might be worth buying and trying out. His axe is two weeks + pay for me plus shipping, cant afford to try one. fiskars is around three days pay for me, that I made an effort to afford, completely based on reviews here, and I am very well pleased with that investment. It works as advertised, and was easily 3 to 4 times as productive for me with much less effort. but..thats about as high as I was prepared to economically experiment as well. Regular maul, 15 minutes, thats it, ready to go do something else, fiskars I can swing for hours. proof enough for me, splits about almost the same wood as any maul I have ever tried.
If I was back in my old job pre injury days and raking in 500 to 1000 dollar paychecks, sure, I would try a high end axe or two or three, for myself and the team here, to give a good review, an honest one. Not now though. I have never been cheap, but I am forced to be frugal now, quite frugal, heh. Ill have to leave it to the folks with larger paystubs to try out and report on the higher end tools.
This is also why I learned to work on saws, cheap used, barely or non runners to start with. Same with vehicles, I buy rollers and eventually make them work.