There doesnt seem to be many OC riders or even SoCal. I was trying to find a group myself. Seems to me OC is pretty far away from getting to the less populated riding areas which is probably the reason you dont find many riders or even published routes starting and ending in OC.
What year DL650 are you talking about? When I researched this for a friend, I found lots of you tubes and reports on pre '12's that it seems to work good, but the exhaust is directed differently in the '12 and up models. When he insisted on going ahead with it, I helped him and we cut and drilled. The result was a little more noise, but not a pleasing sound at all.