I run 30 front and rear. Only way to keep my centers from burning out.
And air is over 70% Nitrogen as is. Nitrogen might be a good idea for an INDY car or NASCAR (where small deviations in pressure affect handling), but makes virtually no difference in a regular tire. It's just another way shops can bend you over for even more $$$.
Chrome don't get ya home, but it'll sure get ya laid.
98 Ram 1500 QC SB, 318, SCT Tuner, CAI, high flow cat, headers, Electric fan, 8.5mm wires, 220L Aux. fuel transfer tank, 1500W Circulating block heater, DIY dual batteries with self boost ability.