I've got a Oregon 28ton splitter, and it is absolutely brilliant.
9hp Kohler engine, starts first pull every time.
Have not found anything it can't split yet, and have put some nasty knarly wood through it.
I picked it up for $1650, come with a 3 year warranty.
Another brand that is worth a look is the Redgum splitter, similar price to the Oregon and has a 6hp Honda on it.
I have a few mates who have Chinese brand splitters that do the job well also.
The green Miller Falls 40 tonners are pretty good for the money, I'm just not real big on the Chinese motors.
If you want the best a Whitlands Engineering Super axe is the way to go, but bloody expensive!!
Glenn