Hey, I went federation and am wondering which is good for my playstyle. Armada or vanguards?
I am a in and out kinda guy, I like to move in fast gank a player and leave. At least thats what I do in other games. I need high dps to drop an enemy in a few seconds and move to the next target. I dont care that much about hull strength, but it helps. I need speed as well as dps.
What I got from their descriptions while making my character was that the Armada is Defense and Vanguards is Offense.
I’d suggest vanguards, what you mentioned you like doing is exactly what I do in the vanguards. 
Hmm regarding tenshous post i have to partially disagree:
Interceptors of the Armada are better suited for hit n gank actions since the Web implies a healing debuff.
Attack ships are more or less well rounded on both sub-factions. its situative relevant whether you like to stealth longer or be able to sustain hits in stealth and dont pop outta it.
I also figured out you can fire for up to 2 seconds while stealthing without popping outta stealth.
Regarding frigates, the repair drones of Vanguard are handy, but the rep buff is too small for hit n run, anti missile is giving better survivability in my opinion for a quick strike.
Anyhow, i figure the drones need some work n love, they are more or less useless, since they orbit you n missiles will blast em, n their shockwaves damage your ship additionally.
So:
Gank n Run:
Interceptor: Armada
Attack Ship: doesnt matter
Frigate: Hit n run? seriously;)