Hank writes:

Push vs sef-propelled......... You're not getting any younger. So if
you plan on staying in the house where you are for many years to come,
get the self-propelled. You'll thank me later. However, if you plan on
moving into a condo in the next couple years, get the push.

As others have replied, human propelled is way more reliable.
As we age, we need to continue to be active to stay healthy.

Unless you're dealing with multiple acres, keep your feet on
the ground and keep pushing that mower. If mowing the lawn
tires you out, that's a good sign you need to keep pushing
that mower.

66 now.

Sort of fondly remember the days when there were no motors on our
mowers.

--
Dan Espen