I've had great luck with NGK's in my small engines, never had a problem with fouling or wear. I made a big stink about it when I was younger, every plug in my equipment was NGK. Now that I'm older and wiser I would stick with the OE spec'd plug because its just easier than cross referencing part numbers for different brands, if you make a mistake you could damage your motor.
Personally I usually just clean the plugs for my small engines and use them again. Not because I'm cheap, but because I've never had any improvement in operation when the plugs were replaced. This only applies to plugs that are easy to access, if they're a PITA to get to I'll definitely just replace them with new.
FYI, I use NGK exclusively for my two stroke snowmobile engines, which be tough on the plugs. They are OE plugs on a few different maufacturers and are usually one of two sizes used on most manufactures engines. NGKs are available at every single store near and on the routes to snowmobile trails. I have never had an issue with the plugs and it was always easy to find them.
? I can't say they are horrible plugs for either 2 or 4 cycle engines BUT I noticed the equipment starts much easier with NGK and even Champion, but not as good as NGK. Torch replacement plugs are at least twice the cost of an NGK plug. The NGK plugs are about the same cost as the Champion plugs.
