Macaroni: hard to tell, truly. I wouldn't expect it to have much effect on clean crisp modern monitors, but hard to tell without actually trying it.
The dithering pattern in the nebula gives the image a very retro, scan-line feel.
The ship designs look great as well as the weapons fire and background. It's quite juicy.
I'm wondering what kind of impact the vertical dithering/shading lines on the background have while it moves.
Looks great! Shame the game never got done.
I think this is higher resolution than most arcade games meaning you've put a lot of extra work into doing higher res sprites.