My primary walk mower is a 45 year old 2 cycle Lawn-Boy. Thing is still going strong. Self propelled. Think the deck is aluminum, maybe magnesium. Either way it weighs a ton less than the steel deck mowers. I did grab another gas 4 cycle last year just because it was a great deal. Kohler engine with spin on filter. The self propel on it is not as good as my Lawn Boy.
I've switched to battery line trimmer, hedge trimmer, and edger. Got a couple of battery chainsaws that are the bomb. If had a smaller yard and one that didn't sometimes get out of hand, I'd look harder at battery mower, but I know it would work for my situation