I can only speak for the games I have seen the kit in, so I will do my best.
In my opinion, the flasher kit works best on games that don't go crazy with flashers. I think the GI only option would be best for games like Starship Troopers. I don't think the GI would diminish the flashers in that game at all. Best way to be for sure, take one of your pinstadium sets from another game and throw it into SST.
That's what I plan to do with WCS. I know the kit looks awesome in GOT (flasher effect hooked up to BWMB jackpots to make the whole game Flash green. I'm just not sure how the green flasher will work in WCS since the flashers in that game are used with just about any major shot in the game. I'm afraid it will be a bit too much. And that game has pretty good lighting throughout without the pinstadium lights so I might not need anything for that game.
SST is a very dark game though so it could benefit greatly from the GI piece of the kit. Also, I'm pretty sure the brightness can be adjusted (maybe scott can confirm or deny). That way you can tune it to a way that it gives you the added GI brightness and not lose those awesome flashers.
Also hooking the pinstadium into the flashers in SST will add to the flasher effects already in the game and will probably overtake the added GI brightness the kit gives you.
My official recommendation: treat pinstadium like CDMD. Take it from game to game in your house and try it out to see where it works and where it doesn't.
Remember though. You will need to add an extra magna mount system to each order for each game you would want to swap the kit from game to game. I got three extra magna mounts in my order to help me try this out in some other games.