I wouldn't say they were "slick" at all, Patrice and bunch of other ppl even called em out for it bunch of times. the difference was that since they were all cool/friends it wasn't that serious to them even when they were talkin about serious stuff.
their show was usually the funniest when there was more than one comedian in the studio with em. because most of em were friends and were able to be relaxed, and they were just shyttin on each other. as for the personalities, Opie is just a radio dude, he'll get one or 2 good jokes or arguments every now n then. Ant is more openly racist (obviously) but he's a really good impressionist, like his Reagan & Dice Clay impressions are really dope. plus he's funnier than Opie 90% of the time. him n Patrice talking about racial issues was really good radio. and unlike now on twitter or on his podcast (haven't really watched/listened though) Anthony used to admit when he was wrong or racist etc. more often. Seeing how more openly racist Ant became after he was fired is kinda fukked up though. I guess now that he knows he doesn't have to answer to anyone he's trying to provoke ppl on purpose more. Don't really like him at all anymore
as for the current Opie w/ Jim show, haven't watched/listened to it that much, only times I check for youtube clips is when one of the old regular guest comedians is a guest & I'm sure Norton is also in the studio. Sharrod Small really is not funny on radio at all.
edit. they basically described Ant's & Patrice's relationship (especially when they were talkin about racial subjects) like this: