Bukowski overrated? Is he rated at all? I enjoy his writing immensely, but whether it's Great Art, verbal junk food or something in betwwen is not for me to say.
I first stumbled across one of his books (don't know which one) in City Lights (San Fran) in the 80's. There was a story about being picked up off the street by a city ambulance and taken to a drunk tank. I couldn't stop reading! But it was so effortless and natural that I suspected there was something "wrong" (Great Art takes Great Effort, right?) and so I didn't buy it, and forgot about him until last year.
I appreciate writers who get to the point without a lot of blather - Hemingway (most of the time), Vonnegut.... but Bukowski is the most concise of all. I think what makes his poems work is that he's able, with just a few words, one lone, to subtly turns things around especially his last lines. I've set several to music, and when I started I thought they'd all come out sounding chaotic, dissonant, jarring (I kept hearing very modern jazz in my head as I read them) but in fact they're funny and his self-confidence is rather uplifting, so most of the songs are relatively "pretty".
Sure he's by turns offensive, obscene and disgusting, but that's not really relevant to the quality of his work.
What makes me suspect that his work has Enduring Value is that I often laugh out loud in surprise when reading, the same as when I hear some amazing new kind of music, and sometimes want to read them outloud to myself.