Bandit: Pistols. They've got a decent rate of fire, massive clips and don't really suffer from the terrible reload times that most of their other guns do.
Tediore: SMGs. I do believe we're all quite familiar with just how great they are for second winds.
Vladof: Sniper Rifles, actually. I may run through ammo like nobody's business, but I really like being able to put several rounds down range rapid fire with reliable accuracy.
Maliwan: Sniper Rifles. Normally I'd say that their SMGs are magnificent piece of equipment that I never left Sanctuary without... but that was before I started using Tediore SMGs. Since I now need the ammo for second winds, I'll call Sniper Rifles for Maliwan. And really, what's not to love here? Good damage, good accuracy, a decent rate of fire and high elemental chance. Beautiful. I just wish they made Assault Rifles.
Jakobs: Shotguns. A Jakobs Shotgun is what every Shotgun should aspire to be. Fires as fast as you pull the trigger, reloads in a flash and will absolutely decimate anything that tries to get in close.
Dahl: Sniper Rifels, I suppose. Honestly I don't think I've ever owned a Dahl weapon that was actually better than my alternatives. The burst fire hurt their rate of fire, the guns don't do nearly as much damage as Jakobs. At least with the snipers you're likely to get three crits when you pull the trigger, but even that isn't reliable
Hyperion: Shotguns. What's this? A Shotgun that's accurate from mid to long range? Yes please.
TORGUE: Shotguns. Remember the bit where I fawned over how perfect Jakobs Shotguns are? These are even better than perfect. Your rate of fire and reload times may suffer, but the sheer amount of raw damage these suckers can do more than makes up for it.