Hi Popple

Yes we used to use one as we often used to import games early from the States, I will check what version we have but it was one of the earliest. It worked very well and tricked the gamecube into believing it was American or Japanese very well.
The only game we ever had issues with was Japanese Donkey Konga (sheer genius, J-pop is so much better than UK music for games with bongos

), where it wouldn't let us save the file, but I haven't heard of any other games with issues.
Mark's really the man to answer this question (or GeekBoy if he's around) so hopefully one or the other will come along shortly!