I haven't beaten any of the GB/GBC/GBA games even though I own all of them (although I have beaten LttP on the SNES). It's funny this topic comes up though, because I just started on Majora's Mask last night, after owning it since the day it came out. I beat the first dungeon. I have to say, this one is alot more difficult than OoT. I suppose since there are only four dungeons they had to make them longer and harder. I'm enjoying the game quite a bit though. Better than OoT in some ways, but worse in others.