Nitrogen have good benefits, but maybe not on all tire sizes/cars...
I've always putted nitrogen in my tires for years... And thrust me it worth it ! Even if the "air" is composed of 79% nitrogen the % that they add is a big benefit.
Exemple #1 : They werent able to balance my tires correctly on my 06 Maxima 18" 245-45-R18... When i was starting to drive the morning i had a big whobble in the steering wheel when i was hitting about 70-80kph until the tires get hot, 15 minutes later they were ok. 6 times i've returned to the dealer to have them to correctly balance the front wheels... They even recalibrated their balancing machine... and i've always had this problem until i've inflated my tires with nitrogen.
Exemple #2 : On my Terrain... 19" tires 235-55-R19... When i picked-up the car i've drived like 500km and i was sensing a lot of the rough asphalt... like a grinding sound if you understand what i'm trying to say but maybe not, in the usa you have much better roads than us

. Then Inflated with nitrogen the ride is a way much smoother and quieter. I saw the big difference in the very firsts km i've done after that.
I also put nitrogen in my winter tires... When i put them back at winter, they did not lost a psi... when i was using just "air"... i had to put back 4~5 psi each time. Now, i put them back on the car and drive away.
I dont know where you live for the garage asking 50$ to inflate them with nitrogen... but here in Quebec, Canada, This is about 3$ per tire.
There are also way less temperature variation in the tires when inflated with higher % nitrogen when you start to drive than when the tires get hot.
Maybe there is not advantage with tire size of 60 and more... but with 55 and smaller there is a gain of quality, stability and comfort.
Sorry about my english errors, english is not my primary language.[/color]
This is my opinion based on MY experiences... If you never had nitrogen in your tires, stop talking if you've never tried it.[/color]
Thank you for reading and have a good time

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