If you buy high-quality products, keep them properly inflated, keep your wheels aligned, and rotate and balance your tires as recommended, they will serve you well.
That's really all you're doing when you use nitrogen, you're keeping them properly inflated. You're keeping them properly inflated over a wider range of operating temperatures, since nitrogen doesn't heat up as much as air does, and therefore will be properly inflated at the high temps of highway speeds, as well as when you pull off the highway and they cool down for city driving. In other words, the temperature differential between cold tire pressure and the hot tire pressure of highway speeds isn't as much as it is with air in them.
Nitrogen doesn't permeate though rubber as fast as air, so you don't have to constantly check tire pressure and add a pound or two here or there nearly as often. For example, with air in the tires, I checked the the pressure at least weekly and end up adding 1-3 pounds in a week. With nitrogen, doing it weekly I was actually letting more nitrogen out by checking the pressure than was coming out on its own, so with nitrogen I check them every 4-6 weeks, and it works out that every 4-6 weeks I need to add 1-3 pounds.
So, the tires stay properly inflated across a wider temperature range, and for longer periods of time due to nitrogen not leaking out of the tire as fast as air does. The benefits of nitrogen are exactly the same as the benefits of properly inflated and maintained air-filled tires, only you don't have to be as anal with nitrogen as you need to with air to yield the same results of low rolling resistance and thus better fuel and tread wear mileage.
There are other benefits of nitrogen that we don't much see, like nitrogen means little or no moisture inside the tire. That's why aircraft tires use nitrogen, to prevent the water in the tires from freezing at 35,000 feet. Less moisture also means less tire rot, but that's more for someone who has the same tires on their vehicle for 5 years or more.
Nitrogen isn't the cure-all for overheating tires and the ongoing gator problem, proper inflation is. Nitrogen simply helps with that. Nitrogen is not a scam, does no harm, only does good, and is not a waste of money unless you overspend for it. A 50 pound tire uses about thirty-eight cents worth of nitrogen, cost to the dealer. Five bucks for that is fair, considering the cost of the nitrogen generators and the time it takes to put it in. Much more than that and you're being over charged. I've never been charged anything to have it topped off with a few pounds.
