I have one legendary Maliwan corrosive SMG that is melting shit left and right, but otherwise yeah..
I don't get this "Jakobs only for Shotguns" thing though. Pistols, Shotguns, Sniper Rifles, Assault Rifles...If you get one with enough Damage+ and Crit Damage+ it doesn't really matter which weapon type it is, imo.
Jakob's are really slow to aim and fire with snipers. I think Dahl are the best for speed, accuracy and alt effects with snipers, but that's probably character dependant. Even with a Jakob's sniper, I could never one-shot enemies with Amara...unless they were many levels below me, but then why bother with a sniper when I could just dash punch explode them? With Jakob's shotguns though the story was different, but then I also gain bonuses for being closer.
Honestly I surprisingly love the COV pistols. I have an incendiary one with an +80% blade attachment that's about 100 less gear score than my 3 other guns but I'm still using it as Amara. Super easy to build up Rush stacks with and super easy to Blitz poor mobs with.
I haven't even found a COV gun worth shooting yet, but I did find a pistol a long time ago with 120% melee damage that I would switch to just to punch the shit out of things.
I ignore Tediore weapons like the plague. Hated it in BL2 and still hate it now. Any tediore weapon i come across gets sold on site.
Torgue shotguns that shoot pellets are downright broken in the best way possible. It's to the point that i don't even bother looking at shotguns from other manufacturers.
With Amara at least, some Tediore shotguns are great, because you are constantly running around firing up close and punching, and for the stragglers just out of range, you can reload and the gun
tracks and explodes on them. Torgue are consistently good though with shotguns and rocket launchers (and some elemental based pistols). I wasn't really paying attention to how the stuck ammo multiplied damage per bullet before the explosion at first (so you could stack them until a reload), only that I was wrecking crap with my first one.