TOYBOY89
+1y
Scuba tanks work great, I have been using them for about 7 years.
It can be tricky to get the right fittings to convert the regulator to pipe thread properly, you will have to make a trip to a good hydraulic supply store for fittings, it take 2 0r 3 to adapt it, so I've found.
I always ran an additional 3 or 5 gallon tank, you dont get a lot of flow out of the regulator, but it is always a consistent high pressure. Some regulators have 2 or 3 outlets which helps, just dont tap into the high pressure outlet, unless you are installing a high pressure gauge. most regulators are adjustable so you can get good pressure out of them. Most I have used one at is 225psi, with one 5 gallon tank and there was enough supply to hop it.
I would usually run electric compressors as well, then if your holding tank was empty or low, run the compressors to get it full, then open the scuba to top it up and keep it full. Plus if you run out of air in the scuba you will need to make some of your own air to get you home.
As far as how long they last, they last longer than most regular gas bottles that are filled to 2200 psi, I used to get about 2 weeks or regular use with mine. One tank would easily last a car show weekend with lots of playing or entering an air competition plus hooking up my air bagged couch! Plus they are a lot smaller and easier to move around.