Ok I just spent a few minutes with that pump up can. Seems that with a thin or a thick mixture, it doesn't atomize anywhere near an aerosol can for me. It splatters the paint, but eventually the paint lays down OK. There will certainly be runs.

Im not sure how you got it to spray like a spray bomb after switching nozzles. I tried a few times, once with thicker mixture and once pretty thin. I guess I can try it even thinner.

What I worry about then is if the paint will cure properly. A thick coat with a roller doesn't cure as well (or completely?) as with a thin coat, so if I am getting 1 coat coverage with this spray can, that makes me a bit nervous.

The real spray bomb stuff seems to dry nice and hard, fairly fast though and 2 coats should cover fine. If this doesn't work out, spray bombs here I come.