Does anyone have any recommendations on model, affordability
and efficiency?

It would help to know ...
- the area you will mow (1/4 acre? 1 acre? More?)
- the terrain (level or sloped)
- your physical constraints (do you need a self-propelled mower?)
- your philosophical/ecological bent (do you dislike gasoline engines?)

What do you mean by "efficiency"? Acres mowed per kilowatt-hour? Acres
mowed per hour of your time?

Daniel B. Martin