Ran a game with these guys.
Map here. Scenario rules: The darkness of the caves cuts the range of attack, special attacks, and ranged special abilities by 1. Pillars of Har rules were used, but nobody bothered with em.
Armies were:
Raelin 2
Eldgrim
Otonashi
Velnesh Alphas
Warriors of Ashra x4
vs
Su Bak Na
Me Burq Sa
Marro Stingers x4
The Velnesh didn't do much this game other than get killed by Stingers (who my wife was spamming Stinger Drain with). I hoped to use Eldgrim to help them with their movement, but it didn't matter. No harm done, since Stingers gonna stinger. I did ultimately win the game, but I think that was mostly because of Stinger Drain.
It's good to see that using them as anti-range doesn't always work, especially against high attack figures like Marro Stingers. Generally I think they play kinda as well as you should expect for 90 points. Effective but still likely to die when you don't want it to. I'm comfortable with passing these forward.