I think we brits have to resign ourselves to not having produced many top quality Hip Hop acts, however the 90's Bristol band Marxman are definitely overlooked. I got into them about ten years ago and own their debut on CD (it's quite rare too) and today I managed to find their second album (only an E.P followed) after years searching and it's just as damn good. Their lyrics were very socially conscious and they also had a few tracks with trad. irish music creeping in due to a band members birthplace. If you are into bands like A Tribe Called Quest and Digable Planets then you may like them. I think they are damn good and it's a damn shame that they never made it big. Up's are available.
Drifting (from the debut album):