You can buy a custom axe with the head tempered by Bavarian elves and a handle made out of left over Stradavarius wood, but you won't find an axe or splitter that does better than the Fiskars brand.
And they are inexpensive.
I have the shorter "boys axe" that I carry in my trucks, and the same size splitter and a longer full size splitter. Best I've ever used in all cases.
Casey
+1. I've got a Fiskars X17 splitting axe and it has worked great. I like the shorter handle because I have a shed for wood storage and I can swing the shorter axe inside without hitting the roof; it also gives better control for splitting down small pieces.
