Do you mean push propelled? I’m not sure on the terminology, but there are some where the engine only turns the blade, then there are some where the engine turns the blade and drives the wheels.
I’m guessing you mean something you walk behind but where the engine drives the wheels?
For that money you should be looking at something with a B&S, or better still a Honda or Kawasaki engine. I’d also advocate an aluminum or ABS deck/ shell rather than steel. We did a comparison and went for the biggest engine quality in the width cut we wanted.
Lots of the generic ones share parts. if you will be doing any required work yourself: make sure you can get parts easily, this is something that has caused us issues: we have to go via. a dealer and can’t find the parts easily on the internet.
I think unless you go top-end most with mulching facility will be a combination, I think the only difference is really the blade, but most mulchers seem to discharge to the side: not really sure why.