I picked up a new 20# cylinder and regulator as the 5# will always run out at the most inopportune time (just like the propane bottle in the middle of a steak or a wort boil).
Anyway, I got my regulator from Micromatic, it's their premium double gauge model for $46. Being able to adjust the pressure with the turn of a knob is well worth the $10 difference between this and their cheapest double gauge regulator. This rocks!
Plenty of gas now for force carbing, keg transfers, and purging carboys, kegs, and bags of grain. All for $2.00 more than filling a 5# bottle. It will start to pay for itself pretty quick when I add in the cost of gasoline plus travel time to get a 5# bottle filled.
It shows 1,000 lbs at room temperature. I wonder if that's full?