Number one on my decision tree would be engine manufacturer. I burned out the Briggs that came on my 20T splitter when I got it 30 years ago from Northern Tool, replaced it with a used Honda GX200 about 20 years ago. Heavily used, that threw a valve a couple years ago but good parts were easy and reasonable and it still purrs. Handles everything I have ever thrown at it except a couple of large ash crotches when it was new and I was young and uninformed. Read up on the engines that are offered on any of these splitters, lots of informed (and un-informed) opinion out there, but my money is on the GX series Hondas, some say the GC series aren't up to top Honda standards. I gave my old Yamaha tractor to a strange, savant-like kid a couple of years ago who was well versed on engines even though he looked like a homeless slacker type, and he warned me about replacing my tractor with one that had a Kohler engine as they had many well known issues with oil leaks and the like. Lots of history about place of manufacture and assembly standards on those engines, I didn't listen and picked up a slightly used Cub Cadet with a Kohler engine and it started smoking from oil leaking on the hot bits an hour into the first mow. Luckily I was able to return if for full refund from the dealer (see Woody5506 above). My buddy sold me a 15 year old Simplicity with a Honda GXV530 and it is rock solid.