I have both and while I've never done a true side by side, the flat '50 is a pretty ballsy Tele pickup but the Piledriver is even hotter and more in your face. Neither, in my opinion, are great with the really trebly "twang" sound that a purist will love (although the '50 is closer to it than the PD), but that's not what I'm after. The '50 is great for blues, classic rock, some AC/DC, and is passable for metal (I dig Metallica and Slayer). The Piledriver is even less suited to the twangy stuff and imho can do rockabilly and country, but you'll probably have to work a little harder to tweak your tone and volume and maybe use a treble bleed. If I were into jazz or country or rockabilly I might pick a blackguard from one of the eras that has greater focus in the treble and more vintage output than the PD. The '50 can do those but it's not really that twangy relative to the others. Just my two cents.
