I use the belt-and-suspenders technique for my round gauge panel.
Before I exit the aircraft, shutdown checklist includes "Master Off" (and "key on glareshield.")
If outside, I touch my master switch- far left end of the panel- to be sure it's down/off before fueling, tying down, or connecting the towbar for hangar entry or exit. (I also sight the key.)
Redundant by design, one catches omissions in the other. That's also why I put "flaps" in both post-start and pre-takeoff checks, after an unplanned "soft field takeoff"
