Hey Spliff,
I didn't see this thread until today. I can answer all those questions, or try to at least. Initially the rumor was that the retail release of Cubrar / Tekour would have both the black and red heads. Once the figure was released we learned just how cruel FPJ is by releasing both versions without any hints on which version you are getting. As you already mentioned, so far the "ginger" Cubrar seems to be the rarer of the two versions. I recall seeing the "hidden version" phrase to describe it being coined somewhere on the net. I actually created a new listing for the red-headed version, which I listed as the "variant" of the black-headed Cubrar. As for the Diaclone release of Cubrar, yes he did come with two heads and an awesome magnetic Diaclone Driver.
Hope that helps.
--SoS