6k Nitrogen tank

So I am thinking about leasing a nitrogen tank to fill my line of FX airguns. It is compressed to 6000 PSI, has anyone tried this or have any suggestions for a good fill station or safer options. It will cost me $64 a year to lease the tank. And $17 to have it swapped out. It seems like a good option when you consider paying thousands of dollars for an air compressor. Any input would be highly valued.
Who are you using as a supplier on this