yeah, pretty much. i try to use a white primer if I am painting light colors just so it doesn't take as much to cover and the coat of paint is as thin as possible.
Make sure you let your primer dry for at least 24 hours (48 is best) before spraying metal flake over the primer. The primer will bleed off solvent underneath your metal finish.
The Tamiya white primer is great but it stinks like hell and is expensive. I usually warm the can before I spray it so it improves the performance. Warm (not Hot!) tapwater in a bowl and stick the can in it for a while. It will spray a much finer mist. That works with any spray can so you get a finer spray with less build up.