Some Karachities speak very refined Urdu, the pure sakeel Urdu though. Urdu is a beautiful language. Can outshine any other language if spoken properly with right words.
Yep....jeera, jindagi, jabbardast, are nails on a chalkboard for us Pakistanis, but melodious-sounding to our next door neighbor. It deserves a thread of its own. In the meantime, the only way to fight back is covert the j's to z's.