Also I've never heard the Joan Baez version but Judas Priest's cover of Diamonds and Rust
is one of my favourites for sure. I'm not usually big on live albums but Unleashed in the East is great from beginning to end.
I checked out the Maiden covers although I hadn't heard of the bands. The Iced Earth cover was awesome and pretty much exactly what I meant about staying true to the original. They nailed it and I hate to admit it but the heavier guitar almost sounded better to me than the original. I actually wish Maiden's rhythm guitar was heavier but I guess you can't ask for everything.
Yeah, Iced Earth released a tribute album called "Tribute for the Gods". It's definitely a nice change of pace and takes the best of melodic heavy metal (I don't think they're quite black/death metal) into NWOBHM, which is more speed intensive. I like Matt Barlow's voice too as he adds more of an emotional twist that Bruce Dickinson doesn't focus on.
Forgot to say that they do a great version of The Number of the Beast
The Aces High cover I didn't like as much mostly because I just can't used to that style of singing. It was weird to hear Maiden sung that way.
You mean Children of Bodom? Well, they're melodic black metal, but they have elements of Iron Maiden, Dream Theater, and the gravel-like voices you hear in death/black metal and it's a nice sinister black metal rendition of the song. The vocalist (Alexi Laiho) is an even better guitarist.
CoB also did a cover of The Ramones' Somebody Put Something in my Drink
, but it's a bit silly anyway, thought nowhere near as silly as them doing Britney Spears' Oops I Did It Again.