I've used electric lawn mowers for many years, including ones with electric cords, non-self- propelled cordless ones, and a self-propelled one. Three years ago, I bought my first self-propelled electric lawn mower from Amazon (the Black and Decker-19" SPCM1936). When I bought it, I had high hopes, as I was disappointed with the battery performance of my prior electric lawn mower. The Black and Decker model came with a very large, and heavy battery. It seemed to perform well the first year. However, I started noticing some problems at the end of the second season. Finally, I bought a new battery during the third season. Depending on how high (or how wet the grass was), I could get anywhere from 30-45 minutes on a single charge. However, after the third season, I noticed that the left rear wheel started making a very loud grating sound. I could still use the lawn mower, but the sound was very distracting and annoying. Because of the problem with that wheel, it was difficult to manually back that lawn mower up. I knew that it was a matter of time, before problems with that mower, might become worse.
Finally, I saw an ad on television, regarding the new Ego self propelled mower (21"). Prior to buying it, I became familiar with that product, through various instructional videos on U-tube. Hence, when it arrived, it was as if we had already been introduced. I've observed a number of advantages which the Ego mower, enjoys over the Black and Decker one; they are as follows:
1- It is much lighter, and easier to turn over, when it is necessary to clean the blade and the undercarriage;
2- It is much easier to maneuver;
3- The self-propelled motor allows the mower to go faster, than the Black and Decker one.
4- The Ego mower has a longer running time (more than one hour);
5- The battery is much lighter, and smaller;
6- The recharge time is far superior, as it barely takes ten minutes to recharge. It took well over an hour, with the Black and Decker mower.
7- I like the longer 21" blade, as opposed to the 19" blade.
The only thing that I don't like about the Ego mower (in comparison to the Black and Decker product), is that one has to remove the battery from the mower, and insert it into the charger, and vice-versa. The latter procedure was not necessary with Black and Decker, as a charging cord would attack to that mower, with the battery still intact in the mower.