I absolutely abhor enamel primers. They NEVER sand decently and always clog up sandpaper whether dry or wet sanding or even with sanding film.
Primers should be lacquer based, PERIOD !
Kilz is technically not lacquer based but it is not an enamel either and fills/sands well.
Lacquer primers work with ALL topcoats, enamels and Kilz do NOT.
I only use Kilz if tube spirals are very deep and I intend on using Enamel topcoat.
Usually I topcoat with Aero Gloss or Brodak dope shot out of a spray gun, necessitating a Lacquer primer.
The best model primer ever was Pactra Prep.
Was dope/lacquer/enamel/urethane/epoxy compatible, dried quickly like dope, filled almost as well as Kilz. Unfortunately it has not been available for over 20 years. I'm down to a quart and use only very sparingly. Brodak primer is almost as good though, but you have to have a spray gun or airbrush.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !