Went to the "getnitrogen" link above, and noted that they touted Consumer Reports as an endorser of using it. Then went to the CR site and read their article, and follow up comments. Not sure if you have to be a subscriber to read it (I am), but here's the link: https://www.consumerreports.org/cro/...tudy/index.htm. In sum, they looked at PSI changes in 30lb filled tires over one year. With air, the tires lost 3.5lbs. With nitro, 2.2lbs. This did not look at longevity or other touted benefits of switching. Nor did it try to duplicate on-the-road use. High pressure tires might have different results. They did note that they estimate that using nitro adds about $5 to the cost of new tires, at locations offering it (which is where the "making money" statements come from). In their test, their generating equipment only supplied 95% pure. Presumably that is about what other places acheive, also. In a follow up note, this seems to sum it up nicely: "The positive benefits of nitrogen in high(er) service pressure applications, such as used in large truck tires, has been documented in the industry. Our test centered on passenger tires, only. We are not discrediting the use of nitrogen, but it is not a substitute for regular inflation checks."
So, if you only check tire pressure once a year, then nitrogen may be for you. But it appears we are discussing angels-on-the-head-of-a-pin for the average RV user. If easy to get, go ahead and use it. If not, seems to not be worth the extra effort. Better to worry about how accurate your pressure gauge (or TPMS) is, or what tires give better service life. And check pressures regularly.