Finally
 

Figured out how to get my garage going with fuel reports and such.
Last tank was best ever at a shade over 39 mpg. It came easy, too easy, and I swear I drove no different than any of the previous tanks. But, this is the first tank with nitrogen in the tires and it made me want to ask what you guys noticed about it.

Nitrogen offers no fuel economy advantage over regular air at the same pressure.

Congrats on choosing the 6-spd manual over the automatic though. I wonder what ratio of Sonata buyers are doing that...

I say the ratio is small, the dealer only had one of another color and had to trade another dealer for mine. The pressure is the same (checked after the fact) but the car seems quieter, smoother with less road noise.

Air is mostly nitrogen anyways, so I don't see why it would offer a bigger advantage...

Placebo. Works for me!

Unless you're getting your tires up to very high temperatures (i.e. racing), you won't notice the pressure change due to water vapor from shop air in your tires.

You could always just as for a 70% nitrogen blend:P

Now if you add some extra PSI to your tires, this is a different story