My take on this based on driving with both...
Nitrogen filled tires are somewhat pointless from almost every "expert" I have spoken to. They produce a stiffer, harder ride and there is barely any difference in tire life etc. Ask any tire shop and you'll find many don't deal with Nitrogen. It's something auto manufactures do to make us think it's better so they can charge us more. it's more of a catch phrase than anything, if we drove Ferrari's - different story.
The only area they are better, the sidewalls are stiffer so if you're tracking, then yes, Nitro for sure.
For the other 99% of us though - they make a loud, harsh ride.
I flipped mine to air filled right away, got rid of the Pirellis and went with BF Goodrich g-Force KDW's and I couldn't be happier.
Cheaper, better traction and quieter. All win.