But just MHO...

me wrote:

I need a new 42" riding mower.

I'd like to have a 9'ish bushel bagger so how many horses
do I need?

Minimum, about 12 to 14. More is often better.

I do not want bells and whistles. I want a mower that will last
about 10 years and cut grass.

Well, you can buy one 10-year John Deere for WAY too much
money, or three 5-year el cheapos from Lowe's/HD for the
same amount. (Inflation considered; and those three would
likely still cost less than the one JD.)

Skip the automatic transmissions completely, but make sure the
clutch is a separate pedal from the brake. (Today, most
of them have the throttle on the "dashboard" - and enviro rules
require running flat out. I'd like to choke the idiot who
designed the "clutch/brake". Nothing is so much fun like going
to fifth gear - and always from a dead stop....)