Over the years I've gone through dozens of mauls, some of them had wooden handles, some has fiberglass handles, one even had a metal handle, on every one of them, without exception, the head got loose on the handle and eventually came off or broke off within a couple years of use.
What I like about the Fiskars, and what sets it apart is the way the head is fastened to the handle. I've have two Fiskars for 3 years now, the X25 and the X27, and neither one is showing any signs of the head coming the slightest bit loose or the handle breaking.
My only complaint about Fiskars is that they don't make one with a really large head on it like a proper splitting maul. Their largest head, the X27, is more like a large axe head and is only about 4 pounds, although they don't give the actual weight of their heads for some reason. It still splits quite well, but I'd like to have, or at least try, a Fiskars with a 6 or 8 pound maul head on it.