Other than that it feels very similar to WoTLK Gold how Shadow Priests have played for a long time , only a little more speedy playing back, well, no, really. It's not something most people would be seeking out However, you'll definitely be interested in Shadow Priests for an exception, but usually not more than that.
But utility they're still good however their purpose has transformed since TBC. They were famous as mana batteries, they replenished mana in huge quantities back to their team after the course of a fight. Then in Wrath this mana regen effect has disappeared and instead they're replenishing and you'll need two players playing this 25 Man raid to fully benefit what they bring to the table. What makes them special is their dispersal effect which has a 90% damage reduction.
If there's a huge soak mechanic, you can toss your Shadow Priest to it and it will more or less guarantee going to fight in PvP. The spec also gets improved with a lot more damage CC and survival. They have a disarm from the psychic terror the typical AOE fear and silence that they've always experienced. Now, the in slowing down effects. Dispersion will assure you that you'll get something . If you're able to get vampiric twits can be dispelled cheap WoTLK Classic Gold now, it will hit the target in the back with force.