+1 on this. The PW stuff just isn't burned into my memory the way the "regular" rock/blues/rockabilly tunes are. While I like some of the PW tunes and especially enjoy guys like Lincoln Brewster, the truth is I don't listen to PW music much outside of learning it for the gig.
Also, as Pacman mentions, if it's a fill-in gig, esp. with short notice or some odd arrangements I might use some charts. I generally would prefer not to use them in a rock/bar band situation, but if I get a call on Tuesday for a sub gig on Friday I'm gonna have to cheat a bit. I'm not a pro, and I have a day job.