While testing a few strategies I found that the computer companies heavily favor import over other company products
I was selling frozen chicken of higher quality and lower cost than the import, yet I only had 4 out of 14 companies buying from me, my warehouse was right next to the seaport and the same city I was in had the import, so the shipping cost would be within 2 cents difference anywhere in the world.
I had 10 cities and 50 companies in the game.
My value was 139, while the import was 110, the import had over 2x demand for supply, while I had about 1/10th demand to my supply and sill they wouldn't buy from me. I sped up the game and even 2 years later they didn't change, until the import quit coming in.