Knockoff DAVV 100L/min, 3.5cfm compressor. Half a dozen expired CF rescue tanks in various sizes, 30, 45 & 60 minutes. I would grab one every time I ran into a good sale price (between $40-$80.)
I had been refilling 3 60 min aluminum tanks (3000 psi) and a single 30 min CF tank (4,500 psi) but was going through air way too fast and all the trips to fill became a major annoyance. This was especially true as more of my PCP's filled to higher pressures and even using the CF tank to cascade after filling with the aluminum tanks I'd run it down in a single session of shooting. Now with a half dozen CF tanks I can easily go two weeks before needing to haul the compressor out for a refill session.