Pure White - What colour primer?

I need to ask a quick question here; i'm going to paint my current project in Tamiya Pure White spray, the problem is i don't know which colour primer would be best to use first. I already have a grey primer so if i used this i wouldnt have to go out and buy some white primer. But ive been told that white primer would work better with white spray paint.

Any ideas?

White primer is a must for white, yellow and all other light color.

if you use the gray primer, the final color will be grayish

White primer works ALOT better for lighter colors like white, yellow, red, and orange. The only white primer I can get locally is Duplicolor, though, and only Meijers stocks it, none of the auto parts stores carry it!

Don't be tempted to use grey, the ple colors jut won't cover it properly. It's much better to use white even if you have to mail order it and wait. I just keep both in for what ever I need to build.

About the lightest color I would use grey primer with is red, as it will cover but will take some of the brightness out of the red which can be useful for things like 1950s Ferrari sportscars.