Uh, not sure about that "cures rock hard in 20 minutes" claim. Even
BSI's summary page says to wait 8 hours for full cure. Some
reviews on Amazon said it takes any longer.
That said, it might still be a good option. If you do try it out, please post your results. How do you apply it? How many coats needed? How much weight does it add? Apply before or after assembly? Etc.
BTW, if you're doing LPR, I still recommend papering as a *much easier* way to achieve smooth fins. I've documented my technique with Avery label paper a number of times in my build threads (I'll dig up links if you want). I find it to be *so much faster and easier*, and it adds a good amount of strength as well. It doesn't work in all situations and it does add some weight, but it has become my first option.
Their official garb seems to be pearl-white...