Things I liked:commonality - these are an easy fill. Everyone knows where their local firehouse is - not everyone has a dive shop in town for filling scuba bottles Things I would have changed:nothing - I wear one of these on a daily basis. They're lightweight, extremely durable, and very capable of filling an air rifle. What others should know:These were designed for firefighting - not air gunning. That said, most firehouses will want to see a hydrostatic test date after the bottle is 3 years old. The price isn't going to come down - it's designed for something else. If you opt in to this tank, you should be able to use it for about a year, on a single charge, shooting 15 targets per week.