Vanguard: Taunts, Grapple, Stealth scan, 10m Burst Dmg, aoe 3sec stun, 4m interrupt
Commando: 360° aoe Knockback + 5 sec slow, Stealth Scan, Cleanse, Off-Heals, 30m Burst Dmg, 30m interrupt, 8sec/30m mezz, rediculous amount of AOE,
and if specced gunnery: 4 sec Root and 70% slow on Full Auto (which helps your Team when focusing or peeling off)
Are you serious?!
AOE damage is completely overrated. AOE damage doesn't take down 2 healers. AOE damage on the scale of 2k per target, doesn't even compare to smash. A cast heal that consumes ammo, takes 2 seconds to cast, is interruptable and is almost entirely useless 95% of the time. The knockback seems great - until you realize you just knocked them all back to leap range as you're rooted/smashed to death.
Gunnery is a worthless spec in PvP. I know some guys can do well with it, but they are certainly not playing top tier players. Every time I see a Merc against me spamming tracer missile, it fills me with joy knowing just how much I'll shut him down the entire match. The only way they are successful, is against a team that anyone would have beaten. The dependence on cast times KILLS the class. The range of the attack means nothing when it takes longer to cast a single attack than it does to close the gap. Sadly, that's the biggest problem with this spec is just how flipping stationary it must be.
The ONLY thing a Commando has going for it over Vanguard, is the 30m interrupt. Otherwise, Vanguard is undeniably better and more team oriented.