Really? I don't feel like listening to any versions of FOTD other than Rock In Rio.
Some other examples (my opinion, ofc):
1) The Evil That Men Do on En Vivo is the best live version from the song and I don't feel like listening to any other. Maiden England's version is particularly bad compared to En Vivo's.
2) The Trooper from En Vivo is also the best live version from the song, although it's ok when I listen to LAD and Rock In Rio. But still, En Vivo is better and if I want to listen to The Trooper, that's the album I pick for a listen.
3) The Prisoner from BOH is the best version of the song BY FAR. On this one, I don't feel like listening to it anywhere (Not a fan of studio version anymore and not a fan from Maiden England's either because of the slow tempo).
4) Blood Brothers from RIR is the best version of the song. En Vivo's version is ok, but they added too much keyboard on the last part of the song, which annoys me very much.
5) Hallowed Be Thy Name from RIR is the best version of the song. En Vivo's version is very good, Flight 666 is ok, but the rest sucks for me, especially LAD and BOH. Not a fan of HBTN live during the 80's. I can take the studio version, though.
6) Rime of the Ancient Mariner from Flight 666 is the best version of the song BY FAR. I don't feel like listening to studio + LAD version at all.
Man, the list could go on and on... I might make it all when I have time.
Nice thread, by the way.