I think having the availability would be a great asset. Thing is, there's more cases than we might think where someone might need to rent a tank. Forgot it in the basement, found out the reg on theirs has gone bad, forgot to get it hydrotested (guilty of that once or twice), have a 3k and would rather have a 4.5k for the final battle, have only ever run CO2 and would like to try compressed air before shelling out the purchase price. The list goes on and on. It's a great idea.