When asked to both cross over to another plug manufacturer and change heat range, the guys behind the parts counter have been known to cross reference plugs to NKG and get the wrong heat range. Most brands don;t use the lower-number = cooler range. But the important thing is not the number or brand name... it's how the plug works in your engine.
I use 4oz/gallon.. a 32:1 mix. When i disassemble the engine there's a nice coating of oil on all parts.. i get no exhaust smoke after the engine is warmed up .. no oil ever drips from the tail pipe... so i'm happy.
The consequences of running with not enough oil are pretty bad and i have no interest in cutting back on oil for no good reason.
Just like with the plug heat range, type and gap, the fuel:oil ratio is not written in stone. .. milage, wear, riding habits, terrain, state of tune, etc., can all make a difference and may indicate something other than what is generally recommended is needed.
Nobody knows what a particular bike needs better than the knowledgable, informed bike owner who determines things for himself.