I bought a cheap, Chinese MIG welder and needed some C25 gas. I wanted a cylinder in the 80 – 150 cubic foot range. I checked Airgas first, since they’re less than a mile away. The next day, I stopped at Industrial Welding Supply and was shocked at the price difference:

Note: If I remember correctly, the prices for Airgas were for a 125 cubic foot cylinder, and the Industrial Welding Supply prices were for a 130 or 135 cubit foot cylinder.

So, renting a bottle for one year at Airgas would cost a whopping $420 per year, plus fill costs! By comparison, renting at Industrial Welding Supply will be only $60 per year, plus fill costs ($38 to fill with C25). Obviously, I’m going with Industrial Welding Supply. I went with a monthly rental because it only costs an extra $8 per year, and doesn’t require opening a full-blown account. The rental just requires a basic credit check (SSN, drivers license, address, etc.) that took five minutes. The $5 monthly bill is sent out as an actual paper bill, which is a mild annoyance, but somewhat adorably quaint.

Incidentally, on the subject of leases, I was told at Airgas that if I returned a leased bottle after a partial year (e.g. three months), I wouldn’t get any money back. Industrial Welding Supply told me that they pro-rate partial years.

Another minor detail: Airgas mentioned that they only do bottle exchanges (i.e. owner bottles, not rented or leased) up to 80 cu ft, with the odd exception of 150 cu ft. So, they’ll sell you an 80 cu ft bottle, and they’ll sell you a 150 cu ft bottle, but they won’t sell you a 125 cu ft or a 300 cu ft. It’s a weird exception, and may vary by location.