In "Must EMTs and others rend Kriyah each time they see a patient die?", Chalutznahal cites Yoreh De'ah 40:5, which says that when I witness a fellow Jew die, I must rend my shirt out of sadness. And British Rabbi Dr. Moshe Freedman brings this down as practical Jewish law.
Is this still the prevalent practice among Ashkenazim in North America nowadays? And if I'm wearing a shirt that I like, can I change it before rending k'riyah?