So recently, I bought another AN505BK Twin Famicom because the other apparently had a PPU problem and had screwed up graphics (but that's a different story)...
I'm just notiing one has the FF logo next to the cartridge slot and the other one doesn't. Do I have a variant?
(http://i8.photobucket.com/albums/a13/Oldschoolage/Mobile%20Uploads/image_zps2tmpnfc1.jpeg)
The FF logo console is probably just a later revision, similar to the FF and non-FF Famicom originals.
I have no idea if their internal board/CPU/PPU revisions were changed, I only have the non-FF Twin Fami to compare.
Why not to open both cases and compare?