For years, it's seemed, most hip-hop acts receiving good notices in the mainstream and alternative media have subsequently been rewarded with middling album sales and dim futures -- which is one of many reasons why the rise of OutKast, appearing Friday, March 30, at the Fillmore Auditorium, with Ludacris, has been such a joy for guilt-riddled scribes to behold. From the first few bars of the act's debut salvo, 1994's Southernplaylisticadillacmuzik, it's been clear that this Deep South duo -- Dre (Andre Benjamin) and Big Boi (Antoine Patton) -- wasn't interested in simply regurgitating the beat styles of the moment. Moreover, its next two discs, 1996's ATLiens and 1998's Aquemini, found the pair striving for new musical highs rather than settling for the same old ones. That's a dangerous strategy in a commercial rap scene that seems to prefer repetition over innovation. Yet OutKast's latest, the endlessly funky Stankonia, has not only gone platinum three times over and spawned one of the best hit singles of the past year in "Ms. Jackson," but has also shown other acts that letting your freak flag fly can pay. Pray that at least some of their peers were paying attention.