Blue...maybe red (but red is probably a little too permanant - use red on things like traveler hardware and things). Green is for things you don't ever want to get apart again.

You know, a LOT of boats do just fine by taping their rings and pins without any issue. IMHO, it's a system that works just fine if you have good quality rings and inspect them occasionally (as with anything). I've gone thousands of trouble free miles and several years with it.