Are you splitting pine? The kind of wood you split makes a big difference. I built a 20 ton and wish I had bigger.

This is true too. Wood type and how dry it is when split make it split different as well as size. The amout of wood you plan on splitting changes what you need also. If you want a pickup load is way different then wanting 10 cords.

Well, some pine but I have ash and cottonwood to split also. One thing to remember I don't need to do two or 3 cords. This is at a remote area and anything that is easier on my shoulders from running an axe or splitting wedge would be nice.

Since you've added cottonwood to the conversation I'd go with a big vertical splitter as cottonwood is a royal pain to split until it's very dry or if it's well below zero when you're splitting it which I'm certain that you know how stringy it can be when it's damp or wet .

Buy once cry once but save you're body a little bit of discomfort from having to swing a ax ! In the long run it will save you money when you're splitting 18" pieces of wood .

Wood splitters and wood stoves. Buy the heaviest one. Pay a little more up front. Easier to sell if you get done with it.

In gas powered there are 2 primary types

inertia and hydraulic

inertial if you have all knot free logs less than 16 inches in diameter you will make better time , but they do wear parts
the DR logs splitter is an example of this it has a fly wheel that is turned by a belt and you press the lever and it puts a shaft that grabs that fly wheel into the gears and splines and slams it into the wood very fast

if you have knotted up or larger logs , 22-28 ton hydraulic all the way

I am running for the last dozen years a 27ton vertical/horizontal dirty hand tools brand.

things to watch , you will eventually need to replace the love-joy connector between engine and pump how hard poor the layout of that and low pressure side of the pump supply line can cause grief.

I suggest storing inside or covering your engine , my biggest issue is the gas cap design let water in the tank if it has snow setting on the tank , a peice of tin to shed all the snow and rain from that has made a huge difference. I would have to drain the tank and carb often before.