I'm going to change up my formula here and put the cover first because there's a bit of a personal story for me here.
Turn the Page: Metallica (Cover)
This is the first version of the song I heard. I mostly got Garage Inc. for "So What" and started to love the other songs that came with it. This one was very near the top.
Bob Seger: (Original Singer, but a live version)
Now of course I knew it was a cover, so eventually I wanted to find the original. But like, I heard the name the name Bob Seger before, but I never really listened to any of his stuff. But then I got his greatest hits album and "hey, I know that song. I know that one too. And that one. And that one. Holy crap! I know like 90% of these songs!
But here's the thing. This greatest hits album had a live version of this song. It had studio versions of all the other songs, but Turn The Page was a live version. It was good. It's better than good. I absolutely love it. But then what's the studio version like? I want the studio version. But everything on iTunes was live versions. I had to really hunt for this studio version.
It turns out Bob Seger doesn't view this album very favorably and has long since stopped selling it. It was absolutely impossible to find any authentic copies of the album and actually pretty difficult to get any bootlegs. So I really lucked into finding a copy on Amazon for $30 (which they're sold out now, so don't even bother looking. I'm pretty sure the copy I have is a bootleg...but hey! I finally have the studio version of Turn the Page. It's a very different feel from the live version above. It kinda takes some getting used to if you're used to the live version. But it's actually pretty good.
I'm not going to get into whether Metallica or Bob Seger's version is better. That shit don't even matter. What matters is that they're both bangers and I'm glad to have all three of these versions in my library.