Do you still run OEM tires on your car? They weren't made by Nissan.
Gates makes just as good a belt as 'Nissan' does. This is one of those things that aftermarket can definitely be as good or better then OEM. For power steering hoses and water pumps and that sort of thing it might be a good idea to use OEM (I recommend it), but belts?? please...
Later
"If A equals success, then the formula is: A = X + Y + Z, X is work. Y is play. Z is keep your mouth shut." - Albert Einstein
When was the last time you *really* did something with your Z to call yourself a Z enthusiast?