Well, imo you can't compare these two systems directly, as they use different types of devices to display things.
They both have their legitimation, their fans and haters. If i read it correctly in the forums then things might change when colordmd starts using dot matrix displays.
I have seen it several times, it's not that bad But unfortunately it's still an LCD, so for me no option to put it in any pinball!
Comparing prices, it's also way behind all other available solutions, but keep in mind that they "invented" colorizing DMDs. They also have spent a lot of time and effort on developing, employees to be paid, and so on. I think, you get the point
To be honest, i'm organizing the groupbuys for pin2dmd in europe, so i'm not a huge fan of ColorDMD.
We all do it without companies in the back, in our spare time.
All of you have the option to tinker a bit and build it by yourselves, so all you have to pay is bare the material. No mouth to be fed, no Taxes and other stuff.
I'm sure, if Lucky1 and Steve45 (inventors of pin2dmd) had a commercial attempt, they would do it maybe at an price range that is lower than ColorDMD but way above what they "charge" now for the license key, and keep in mind it's also for charity, they don't keep the money for themselves!
Reliability:
If the LCD is defective, nothing will be displayed. If a single dot is defective, it's dead but all others should still work.
Options:
+1 for ColorDMD. Due to the LCD, they have various display-modes like DotsXL, scanlines etc., a DMD is limited to its dots...
My personal conclusion: buy what you like!
I think advantages and drawbacks are well described for most available systems, support is also available for almost every pinball.
And in the end, it's a hobby
Greets,
Dom