I use the Windstorm by Starmax air compressor
. When using an air compressor, you will need the ABS-3 kit along with an air hose.
The cardstock I mostly use is Neenah Classic Crest Solar White (80lbs). It is a "soft" cardstock, meaning that it is loosely woven. That makes Copics easy to blend. But because it is loosely woven, you have to be careful that your ink doesn't travel out of the line. You just need a bit of practice to know when to stop coloring and let the ink dry before continuing.
It has a very smooth surface. I love that it's thick enough to use for a card base, how it cuts and paper pierces. I love that cardstock.