I am a rattle can user here, with plans to get a airbrush soon, but any ways here is what I use and do.
Primer- duplicolor all the way, I also use wally world cheap primer for when I am doing body and want to see how my work is doing with out wasting the good stuff.
( I want to try plasticote, but I dont have a store near me that sells it)
Paint- for the most part its either Model Master lacquer or tamiya , some times I will use duplicolor automotive paint as well.
I use wally world flat black, and sometimes krylon
Clear - I use ether MM ultra clear coat, or testors one coat clear, I have been wanting to try other brands of clear
I dont get perfect paints job from the can, I have to wetsand then polish, I have a mirco mesh set 3200-12000, I use turtle wax rubbing compond and polish, and then I use meguiars scratch x .
As of late I have been skipping using the micro mesh set and I use 2000 grit paper and wet sand the I start the polishing process.
You have to put in a little work to get nice and shiny paint jobs, meaning it comes down to pre painting prep work, and then during and after work to get those mirror like finishes
If you click on the link in my signature line, you can see my how my paint jobs come, there are not contest worthy yet