You cant get per pixel on anything less than 2 pixels, so yeah point would be better.
If your ship isn't terribly oblong you could try distance(x1,y1,x2,y2). Something like:
system compare distance(bullet.x, bullet.y, ship.x, ship.y) is less than ship.width
or what ever
Distance works off of the image point, so as long as it comes within that circumference it should work.
Other wise the only other thing you could try is instant hit with step, but that would be best with a percentage type of system... wouldn't really work with a bullet hell shump.