If you ask me, it shouldn't be done if you just want to save money. Do it more so you can do fills at home when you wannt bust off a few rounds in the backyard, or tweak your setup.
If you live in an area that doesn't do HPA fills it would also be a good idea. Or if you're into outlaw ball.
One other motive is this:
Most tanks nowadays have a TC stamp along with the DOT certification. Tanks in Canada _must_ have a TC stamp, otherwise it's illegal for any Canadian field to fill it (they and you can both be fined $50,000). It's actually illegal for the tank to be in the country at all. Many people don't realize this. In my area local fields just caught wind of it a couple months ago, and for a while people were getting good use out of their scubas because nobody else would fill their tanks.
Last edited by Aglar : 06-25-2003 at 08:55 PM.