I have N2 tanks at home. Costs about the same to fill them up as CO2 or whatever. I used them when I service accumulators and landing gear struts. It is moisture free and less sensitive to heat. A lot of people use it in their airplane tires. It doesn't hurt a thing but it is amazing when you ask a salesman about "Nitro fill" they have some pretty outrageous claims.
I know some of the PCP air rifle competitors run Helium in their rifles because it expands quicker than compressed air or even N2. Have you priced Helium lately??
N2 doesn't have any downside except it is expensive compared to compressed air and inconvenient for most folks. It's easy for me as I always have a cylinder or two on hand.
