I have had several self-propelled, rotary mowers, mainly petrol, over the last 50 years, but this Mountfield Cordless self propelled mower gives the best mowing performance.
In particular, it expels the cuttings well into the back of the grass box avoiding build up at the front. Mowing my slightly sloping lawns takes 45-50 minutes and, mostly using the mower's self-propulsion, the 80v battery still shows circa 50% usage on completion.
A big design negative, however, is the top-hinged, opaque, battery hatch cover, which lifts up 90 degrees from the side to a parallel to the ground position. This means that, unless the mower is (unsafely) tipped over on its side, or one goes to a kneeling position and then stoops very low (not good in your late 70s) neither the (2.5kg, bulky) battery or the safety key can be seen and insertion/removal of both is a blind and fiddly operation.
Because of this significant inconvenience and the poor battery hatch design, my ratings reflects what, otherwise, would be a 5 star machine.