I'm over in Mecklenburg but I can tell you that Concord PD has now joined the Char-Meck 2D0 system from the Cabarrus Simulcast site. If I recall, the talkgroups do not roam across counties, so you will not hear Cabarrus talkgroups from Mecklenburg Simulcast and vice versa.
I have monitored Concord PD from Concord Mills, but I actually dont have the Cabarrus Sheriff talk groups added to my PSR-800 yet. Next time I'm up at the mall, I'll give it a spin.