Double barrel shotgun and chainsaw, army of darkness doesn't stand a chance. I've only run this solo but it is indeed a PUG carrier and I'm torn between it and UAC5's.
I ran with something similar, but with a 300XL, 2x LRM5s for the added annoying/screen shake factor and moar ammo. Did 700+ damage and 4 kills in 2 matches... Its not bad, but does take time to saw through larger mechs due to less pinpoint damage (hence 4 stars). Fantastic fun on lights... Works similar to a 3x LB10X Ilya.
4/5, Good high damage potential. Works well on most other than Assaults... takes too long to saw through armor compared to other builds.
I agree with the 4 stars, it's just lackluster at first against fresh thick skinned mechs but against lights and later in the match when armor is thinning out it cleans up nicely.
If you want something with a bit more punch to deal with those pesky DWFs... https://www.mechspecs.com/threads/kgc-000-crab-shmack-special-2x-lpl-2x-lbx10-2x-ac5-xl300.7924/
I've moved away from STD's already as I only rarely die from a ST loss. I had a similar build but with LL and more speed, XL325 I think but I love the wub. It's hard to give up speed though.. Trying To talk myself out of getting a XL360. Don't know if I could go 300...