Do AK Interactive Acrylic Paint Need To Be Primed Or Can I Spray Straight On The Model

I generally don't prime my work. However I do wash the sprues with soap and water before I build and I usually rub down everything with rubbing alcohol to make sure there are no oils before  paint.

I also prepare my PE frets by soaking them in vinigar for a few minutes (after taking off any protective plastic covering). They are then washed and dryed. This provides an "etched" surface that allows the paint to adhere better.

I mainly work with enamels but the few times I use acrylics (MM Acryl, craft acrylics, Vallejo, Tamiya) find that a solvent type primer gives the acrylic paint more bite into the surface and better coverage. MM acryl is notorious for lifting when removing masking tape  if no primer is used. Tamiya is the only exception and find them to be very durable paints with excellent adhesive qualities.

Maybe someone that uses the AK acrylics can chime in on the adhesive qualities.

I find when I spray or airbrush without priming the results are a crapshoot, even after washing.  Often it works, especially if I put down a very light mist coat, then let it sit a moment, before putting any more on.  I find more problems with gloss paints than matt colors, and with enamel rather than acrylics.  With enamel I almost always prime before spraying, though I occasionally brush paint on very small parts without priming.