Need you guys to give me some warnings or advice as to it's current usefullness.
I picked one up from an estate sale I was at for 5 bucks. It was expired, but my local lumber yard will fill them for me.
Even with a completely empty tank, they can only get ~3.5 pounds per tank.
Just a couple weeks ago, I filled 3 of these 5# tanks and a 20# tank for a total weight of 28.5 lbs @ 1.05lb = $29.93
That works out to ~$3.67 per 5lb tank. Up from last year, but not enough to worry about.