I'd say I'm an expert Bassist, GGaHT 97%+ on average, every other song around 100% :P I hate playing non DLC songs though so dont play with me if you plan to play the original stuff. I play guitar well (98%+ most songs) but i hate how it sounds compared to bass so i tend to play bass more. I have most DLC but probably only played half of em cause I just got too many to even try to play em all or even tell which ones I have or haven't played.
Also replaying songs on bass to see if I can re-FC them all while only up-strumming! some songs require alt-strumming but the rest i can FC without much problems, actually feels like I'm playing bass for real! Also I can pass blackened on both guitar and bass without much problems, for bass it's easy, for lead solo A is a ***** and requires some OD love but the rest of the song is easy :P
PSN is Bisuto