Just edited the wiki to put in the stratum 6 damage for both guns on Undead which are neutral to pierce (slag walkers for Vanaduke levels 23 and 28). Blitz Needle does more damage. I did not include the poisoned numbers in the wiki, but after poisoning the Plague needle does not reach the unpoisoned numbers of Blitz. Fully heated, no UVs for both.
Plague Needle @d23 vs undead (per shot):
uncharged: 41 before poisoning, 44 after
charged: 72 before poisoning, 81 after
Blitz Needle @23 vs undead (per shot):
uncharged: 57 per shot
charged: 115
Blitz Needle @23 vs undead AFTER poisoning zombie by Plague Needle (per shot):
uncharged: 62 per shot
charged: 137
So if you have a group of with one of each gun AND the mob is poisoned AND if both users fire simultaneously:
44 + 62 = 106 uncharged
81 + 137 = 218 charged
Two Blitz no poison:
57 * 2 = 114 uncharged
115 * 2 = 230 charged
With 3 users the uncharged the 1 Plague + 2 Blitz + Poisoned targets comes in 3 points less than 3 Blitz users (168 vs 171).
HOWEVER: Charged 1 Plague + 2 Blitz + Poisoned Target = 355; charged 3 * Blitz = 345. Poisoned Target wins by 10 charged per shot (@depth 23). Only if you keep the poison up on the target (if you are charge firing constantly you can).
For a main gun: Blitz; especially if you solo. For a 3rd Needle gun on Vanaduke: Plague Needle... maybe. Since I was the only gunner with Blitz and Plague Needle in the group I stuck with Blitz for my fight.
Vanaduke actually takes more damage Needle guns than the Zombies. Charged Blitz Needle does 143 per shot on Vanaduke, 121 on Vanaduke's Zombies (@d28 in other words).
Please search the forums. There have been many threads on this. In a party, the poison definitely helps. When solo, it helps less, so pure damage may be preferable.
You cannot trust the statistic bars in comparing weapon damage or speed.