I think a lot of the negative post are reaction to the outrageous posts about how great they are.
They do work well on some wood, but are no better than most axes of the same weight.
What I don't understand is why folks don't seem to notice the terrible vibrations from the handle, and the claims of "balance". A lighter handle in relation to head weight is no advantage, except in the minds of some users.
For most of the ground work I do, I wear 5 pound weights on my wrists and 10 pound ankle weights and that includes splitting wood. Adding three to five pounds to the head of a splitting tool does not decrease the speed of my strikes. For my evaluation of any tool I don't use the wrist weights.
In fairness, most of my splitting mauls and axes have a total length of 42 inches, which adds quite a bit to the speed of my normal strikes.
I have used the spike driver swing of the young man in the video, in time he may learn a better recovery and be able to deliver strikes in quicker sucession. I have also used the up and down strike many seem to prefer, but mostly use something sorta in between.
The metal is of little importance in a splitting tool that is not also used for chopping or striking wedges.
That it is a single use tool reduces the chances of it going to the woods with me.
I almost never noodle rounds to make firewood; most fisker lovers seem to noodle often.
I've been wondering about the reports of vibration. I have been trying to detect it. No luck, I don't feel anything more than I would with a wood handle, possibly even less.
Harry K