Had a friend try to talk me out of getting this talent, and I'm glad I didn't listen to him. The extra crit chance is very useful, especially fully procced it gives you +3%, but it also helps us desctruction locks, as we tend to draw much more attention to ourselves than the other locks do. I'm only at lvl 2 on this talent, and I'm already getting a pretty good rate at which this skill comes up, about a 1:3 ratio right now. At lvl 3 your chance increases to 25%, which in WoW terms is damn near every time. If you're into insta cast shadowbolts, and don't mind taking a bit of dmg to get it, get this talent. I love it, and you might too.