Speaking of NPftD, I didn't get in to Maiden till after DoD, so I had to backtrack on most of their albums. I held off on this one the longest due to all the bad things I'd heard about it, but eventually I bought it for competitionist sake. I can't honestly say I've ever listened to it more than a couple times. I certainly couldn't name all the songs on it.
And I know I am in the minority here, but I never listen to a song and know, or even wonder, who is playing which solo.