My ColorDMD LED arrived today. I already have a LCD version.
The LCD version is in the STLE and I installed the LED version in my TNG. By default, I found the brightness to be somewhat 'harsh', but after adding a polarised display filter, its just perfect!
In the STLE, I prefer the LCD version. It's a modern game with awesome animations. I use the Hi-Res mode and it really adds to the color experience.
But for the TNG, I like the 'authentic' look that the LED provides.
It all comes down to personal taste, and as mentioned before, some games will look better with the LED and other with the LCD.
One thing I want to point out though: the LCD and LED provide a whole different result. The LED gives more 'punch' and brighter colors, while the LCD provides a smoother display (and the extra display modes of course).
Either way, its the best money you can spend on your pinball machine!