Hi Pianodog,
I'm not an expert, but, in the limited times i've used Vallejo, i've normally used their Vallejo Primer or Tamiya rattlecan primer. Both worked well and i didn't see any issues with the Valljo reacting adversely.
I know some people say the Vallejo primer tends to lift or peel if you mask it, but i didn't have any issues like this, and can only speak from my own experience.
In reality though, i can't see why you can't use just about any primer for Vallejo. So long as it's cured, i can't see there would be any reaction.
Regarding the paints themselves, i'll be up front and say i no longer use them. I wasn't a huge fan. I found that even their "airbrush ready" paints needed to be substantially thinned for the flow that i like. I thinned them by a about 30%- 50%.
I think you can thin their paint brush range, but i've never tried, hopefully somebody else will have some advice upon that.
One last thing - they work best when thinned with their proprietary thinner and clean your airbrush with their proprietary airbrush cleaner. This is another reason i stopped using them, i prefer to clean my a/b with cheap stuff like windex or metho, but they can react with vallejo.
Regards,