Yeah, I think the 70's era Pryor is what most people remember or laugh at most. I've seen early clips of him (Smothers Brothers? Shows like that?) and he seemed timid and not particularly funny.
The albums my Dad had were all from the 70's (early and mid decade?).
I wasn't even that impressed with the Sunset Strip concert/movie (or others 80's televised or filmed appearances). It seemed bitter or off, somehow. And the lighter movies he was making didn't really appeal to me much either ("Superman 3", "Brewster's Millions", a few lame ones with Gene Wilder, etc.).
Many of those 70's albums (with the exception of "Is It Something I Said?") sounded like there were recorded in smaller, more intimate venues (clubs, even...tinkling glasses, audience response/involvement, Pryor playing around with a waitress and placing a drink order in a pretty funny way
), and they're pretty unhinged. May or may not be one's cup of tea, I realize (the language and all), but they certainly made me laugh.
I'm not even sure if they're still easy to find, or even available anymore. I'm bummed that iTunes doesn't carry more of them. My Dad had 4-5 albums. In fact, I recall one being totally devoid of profanity (the others were loaded, of course). But this one, I wouldn't even have to sneak and listen to because it wasn't "dirty". I'd put in on, at 9-years-old or so, with my Mom in the room or kitchen. It was mostly routines on high school, growing up poor, old war movie cliches, etc. I can't remember the name, but that was the one I was openly "allowed" to listen to. It was more like a Cosby album (which they had about 2-3 of too...just funny stories, many childhood/growing up-oriented).
They didn't know, until years and years later, I was listening to ALL of them.
They also had a Redd Foxx album, and I have to say: it made Pryor seem almost like a choirboy. I had no idea Fred Sanford (my only point of reference to Foxx at the time, of course) was that blue. Holy cow, they were ferociously vulgar. My ears melted.