BT, it is the 10 lb tank, and it has enough oomph to fill 40 tires from 15 PSI back upto 30 PSI again, that's why I like PT's.
If you were to run an air tool continuously, it would go for about 25 minutes.
But using the impact to change tires doesn't use that much C02, as it's short bursts.
That vid I had the tank set at 90, and it actually dropped down to about 80 PSI which was to low.
When doing air tools you wanna crank the gauge up about 20 PSI higher than the job requires.
I now crank it to 110 PSI, and when you pull the trigger, it drops to about 90 PSI which is perfect and the tool runs faster.
Just changed over my tires a week ago with it, and it sure is nice.
It costs me about $16 to get the tank refilled locally.
More info
here.