Generally speaking, WAR is the best pulling Tank. However in my experience when I pug on WAR I end up with co-tanks that have the "WAR is OT" mindset, so then I just switch to Deliverance and let them pull (or sometimes I pull and they fight for aggro anyway, so I just Shirk and let them MT).

In 24 mans you should just put in chat if you want to MT, and if someone else runs in and pulls instead then let them have it.