I particularly enjoyed hearing The Damned song “Neat, Neat, Neat” but also loved the John Spencer Blues Explosion song (since I have been a fan since he was in Pussy Galore a million years ago).
On the whole I thought it was a very good movie, with a but too much Tarantino envy, and that was maybe 30 minutes too long (Tarantino envy without the same feel for stylized dialog that QT has but with all the Elvis references).
I also think the love story could have used just a bit more exposition (as much as I love a good ‘love at first listen’ story).
As for the soundtrack, I would say better than Guardians of the Galaxy (which was really just a Boogie Nights rip-off IMHO).