Not to go totally off topic, but I hate that about Praxair(and alot of other CO2 supply companies), the exchange, not refill policy that is. I use a 20# bottle and had a really nice aluminum one that I ended up with after a couple of exchanges and really wanted to hold onto it (until I rebuilt our regulator it leaked horribly, from the day we bought it, so I did alot od exchanges in a short span of time.. I really cannot recommend the Milwaukee regulators). Since it sits in a corner anyways, I just resigned myself to a regular bottle
