We have used Nitrogen in the aircrft industry for a very log time.. Think the tires on the Newell are expensive? But that's not the reason fully. It has been found that the pressures are more stable with Nitrogen and the biggie is mosture.. aluminum wheels corrode... the air dryers are better than nothing however... In my shop it was handy & we set the reguator and filler er up the high pressure was ez.. Didn't need an air multiplier....Our standard was to insure no more than 5% oxygen content in the tires...
if you have clean (no oil) DRY.. (NO MOSTURE) air then you're good.. you'll never know the diff.... unless you winter in Minot and check your air @
-20` and have a frozen schreader valve.....
Here is another link that touts nitrogen.....
http://www.nitrogendirect.com/N2Info.htm
Jimmy