Sorry to say it, but about 2 stars. If you're a big fan of blues guitar, especially West Side Chicago blues guitar (as I am), it's an interesting listen. But there's nothing terribly remarkable going on here.
Willie Kent was a bass player for the likes of Muddy Waters and Howlin' Wolf. Willie James Lyons was a very good guitarist and singer and sideman to some equally famous Chicago bluesmen, but not quite flashy enough to become a front man. So what you have is a band where the front men are both side men. Nothing wrong with the music, but just not enough personality to get its head above water. This album is apparently live recordings, so they couldn't benefit from repeated takes, over dubbing, good mixing, etc.
As a fan of the genre, I'm glad I listened to it. If you are, then give it a try. I recommend "Blue Guitar." If you''re not, then I recommend Melvin Taylor's "..Plays The Blues For You." Same style, much better execution.