What can a 120V Splitter Do? Where Does Gas Pick Up?

Alrighty, so I do almost all my splitting by hand with an 8 lb Maul. I can get through an awful lot, but these low cost (less than $500) electric splitters seem interesting. What is the limit? Can they go through knotty spruce rounds? Elm?

I'm sure they aren't the end all be all, I'm just curious as to what the upper limit is for a machine like this, and where gas powered models pick up the slack?

WEN Electric Log Splitter, 6.5-Ton Capacity with Portable Stand (56208) https://a.co/d/hzpJWcP

 

Those will do a lot, but large diameter rounds are a real PITA on those little machines, and knotty knarly stuff will often stall them.
That one looks to have a decent wedge on it...some have a wedge that is kinda blunt, goes too wide, too quickly, those suck!