Flawless albums... are you sure you want to ask that question, because a lot of what I list are not mastered properly and are still better than most releases today.
Numero Uno: Scraping Foetus Off The Wheel - Nail
To say Nail is a masterpiece would be to undermine J.G. Thirlwell. This album is both simultaneously heart-pounding and racist, while taking any such meaning to be racist with a wry corner-of-the-mouth smile as to symbolize everything is only for the piss.
Number two through ten, well to hell with you, I picked my number 1, what the hell do the runners' up have to do with it?