As the name implies, each track was selected on each volume because they have an 'open' drum break or an element was sampled in a hip hop song. These tracks sound like there were taken from original masters instead of the original vinyl; so they sound great; ready your creative use.
When I say 'creative use', these tracks are perfect if you want to try your hand at sampling your own loops, or widen your repitoire at your next event.
Also, if you are a fan of Hip Hop and sites like whosampled.com fascinate you, these compilations are a worthy addition to your collection.
Now, after all this inherent usefullness,why would I rate this only 3 stars out of 5? The main reason is that not all tracks on these compilations are complete songs. Most are, but some are just the 'funky parts' However, on Volume 1, they really messed up on David Axelrod's 'The Smile' Instead of the larger than life break, they have the last 25 seconds of the song. Bad!!!
All in all, a useful compilation series. If you are interested in HOW Hip Hop beats are produced, this series is a window into the artist's method of creativity.