You probably never drive faster then 75mph, so L speedrated here is the most honest.
The M and N to my opinion are placed on tire to give it a better place in the market.
If you drive 87mph, with the maxload belonging to 128 LI on tire, with the 110psi pressure in tire belonging to the G-load, fat chanche te tire damages by overheating. Driving 75mph with all that, no overheating.
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