People should really go to any festival featuring Sabbath,
Priest, Maiden, etc.
These people are OLD now (heck, Halford is 54 years old).
You never know if you'll be able to see them live again.
1) They could get a heart attack during a live;-)
2) They could break up once and for all.
I already bought a ticket for the third day of the Rockwave
Festival in Greece:-) That includes Judas Priest, Queensryche, Nightwish and Nightfall.