If your willing to experiment and not follow the herd, see if you can find a Champion EZ Start or a Champion Premium.
The regular Champion plugs are NOT as good.
I bought a new Lawn-Boy 2-stroke mower right when they quit making them. They used a NGK plug from the factory in the Duraforce engines.
The Champion EZ Start plug lasted longer. I tried a cheap Champion plug and an NGK and the better Champion offering is a better plug.
Also, getting the correct plug when crossing over to another brand doesn't always happen and people swear off a brand because they unknowingly installed the wrong plug.