Preference is really at the discretion of the user, however as a guideline, the following should assist you in making your choice.
Relatively maintenance free with very little to attend to other than regular checking of your cutting system to maintain safety and superior cutting. The torque (power) is not that of a petrol mower and it is preferable to maintain your lawn well to allow for ease of operation. Freedom of movement is also not equal to that of a petrol unit because of the electric cable which must be used as recommended to assist you in mowing efficiently. Cost of operation is however considerably lower than that of petrol lawnmowers.
To maintain longevity of your engine, no matter how high the quality, it must be maintained and serviced regularly (such as a car) depending on mowing conditions.
Always choose well-branded and known engines such as Loncin, Kohler and Briggs & Stratton, for superior quality and availability of spares. Unknown brands might be cheaper to purchase initially, but could cost you more in the long run.
The power of petrol engines is generally higher than electric allowing you more diverse cutting conditions than with electric lawnmowers, as well as the ability to cut and handle larger properties. Cost of high quality petrol units are more expensive than electric, but freedom of movement is greater.
With both petrol and electric lawnmowers, ease of operation is your most critical element. This is achieved through a combination of superior chassis
The manufactures specified capacity of the grassbox (normally measured in litres), is not as important as the machines capability to fill the grassbox to capacity, which means fewer "pit stops" to empty it. This is achieved by design, a feature Rolux incorporated.
To achieve all this and make gardening a pleasurable pastime, trust in your branded and long standing names