Split,
I've installed over two dozen ColorDMD's on the machines at the VFW Pinball Museum, and the answer is "it depends".
Whenever we convert a game, I play a ball on each of the settings to see which one looks best. For your example of TILE or 8BIT, I found that STTNG and TF look awesome with TILE. I've also used 8BIT on AFM, JD, SS, and RS. AFM is a great example of why you don't want SCAN or HIRES, as those modes won't show the animated chaser lights inside the saucers.
For any of the newer games with video clips (like GOT, IM, or TF), I've found that it's best to use DotsXL or TILE. Having a little bit of black space between the dots or squares helps your eye "blend" the pixels, and your brain unconsciously "fills in the blanks". Any of the fuller settings (8BIT, SCAN, or HIRES) tends to really make the fact that it's not straight video look obvious.
As with anything, your mileage may vary, but I suggest just playing around and see what you like.
Later,
EV
