Murray's hype is mostly born off the incident with Tito (because Tito was the champion and UFC poster boy at the time)
I agree his hype is built up a lot more than he actually ever achieved in the cage.
He has one notable victory on his CV against Rivera (who can't be considered top competition) and a loss to Silva in which he was not knock out or totally outclassed.
Other than that he is far more infamous than he is famous, all the key moments that relate to him are scandles. Stabbed outside China Whites, Fight in alley with Tito and finally caught robbing money and jailed in Morocco.
The bottom line is Bisping has had a great deal more sustain actual success and has been performing on the top level where as Murray never really transcended the lower level Cage Rage status (ok he had a fight in the UFC but that was on the back of his Tito fame more than actual achievement)
So I say you have to give Bisping the edge, we don't really know how good Murray was or could have been because he never had enough fights against top competition to prove his worth.