I prefer the first image of both sides. The other two seem as though they're only lit from the top, which causes the bottom of the coin to look a bit shadowy.
I would say the bottom set. It's the Goldilocks of the three, the contrast is just right. I would like to see more than one light used however. You could try to place them at the 10 and 2 positions.
My guess is the second is truer to the color. i.e. whichever is closer to the true color. However, none are sharp enough for me to see if it is AU or MS.
I would have to say that the third set of photos seems to be the best. The first set just appears too washed out and flat, killing any luster the coin has. The second set appears to have a single point of light set far too high to get meaningful coverage on the surface of the coin. While the last set has the same single lighting source, it appears to have been moved to a more advantageous position, highlighting some of the better qualities of the coin.
