I thought the striker was crap because everyone said it was and everytime I used it, something would go wrong. Then I did its challenge and it was pure love. Even played Plat with it.
Wraith, Claymore, Talon, and Hurricane. I really enjoy a lot of others, but those are my favorites. Nothing in this game is as satisfying to me as disintegrating a Phantom's face mid-flip with a mighty shotgun blast, although melting bosses with a little SMG that sounds like an angry swarm of hornets is a close second.
Easy, there are only a few guns I use cuz...I just love 'em, they fit my playstyle.
Sniper - Valient
AR - Phaeston, Vindicator
SG - Eviserator
SMG - Hurricane, C-SMG,
Pistol - Talon (omg i LOVE the Talon), Scorpion,
to be honest, i'm not a real big fan of any of the AR's yet, i need to practice with them more but i've always been more of a sniper/smg/pistol guy since the first ME
Arc pistol was my diamond in the rough. I dreaded doing this challenge. Ended up using this gun on my MQI exclusively. In fact, I score 50k higher with him almost never tosing arc nades than I did when I harrier/bw with nades. BEAST of a gun.
Also found out I like the graal... alot...
Couple other fun finds go to TSol w/ a GPSMG (love watching the kill feed roll while pug'in gold and knowing people are like 'watdafaq?!') TGI w/ a falcon (weapon dmg on cloak makes those rounds huuurt, then you go boom w/ OL). Viper w/ warp rounds on a biotic (like having a heavy hitting pistol w/ a free scope mod on it!).
Personally it's been the Falcon recently. Just trying to get trick shots with that thing is pretty fun and seeing mooks freeze then do a CE is just really satisfying.
After somehow suriviving a Platinum match (was looking for Silver) with pretty much just the Scorpion I think I might just have to say the Scorpion is my soulmate gun.