3000GT VR4 guys use propane alot. I've heard of a few GN guys running with it too. The GN guys use alcohol mostly though. As far as water injection, that's pretty widespread. You probably won't be able to find an example of each all on one car. You'll just have to mix and match opinions.
Alcohol is the best IMO, it won't rust the intake if any of it's left after running. You can cut it with water, getting double the effect and it's really easy to get either or both of the ingredients.