I am in the same situation, I have already received my regulator and I am waiting for the gas which should arrive within 1 week.
Ar and N are both inert and odorless gases, so technically they work the same way. The only difference in my opinion is the density of the gas, the N is lighter than the Ar so it technically stays easier in the bag and would allow the CO2 to be extracted more easily from the bottom of the bag.
But again in my opinion, from what I've read as long as your setup is fairly well prepared and mastered there should be no differences.
I may keep you posted when I receive the Ar and have done some testing