Are you the shield or the sword?
Personally playing the shield. Vanguard
Thoughts -
Trooper will be an interesting tank for PvP.
(If you've played WoW) Imagine playing a warrior and running up to destroy a ranged.....only to find out he is really a tank. And you just got rocked by tank moves.
If you've played a tank spec in WoW PvP. You know quite well you will be ignored until other targets are dead, then simple nuked by everyone. When not ignored, moves are triggered, rage is generated, and they die quickly.
This will really make PvP with multiple troopers interesting. Especially if the dps spec dishes out a lot of damage and the tank spec allows for some counter moves to the unsuspecting Sith attacking. Troopers might not be attacked first because of this, thus dps/tank troopers mixed at the front lines will truly be an effective fighting force.
If weapons and armor don't differ in looks too much for the two different specializations. Troopers might throw the Sith lines into chaos as well as kick a lot of ass. And even if they do differ in appearance. Troopers being a ranged tank will definitely heat things up and change up the repetitive pace that PvP has started to take.