Calgar Fire Base with Tarantulas?

[Bloodchild]

So i have a bit of a fire base with Calgar on my backline. I find myself with 111 points spare and am wondering if x3 Heavy Bolter Tarantulas OR x3 Aggressors? It is 111points and would like 1 of the 2 to make 2000points on the nose. I think we dont see Tarantulas for a reason, they do have BS 4+ but Calgar would still give them full re-rolls to hit, so hmmm, thoughts?

[Dracos]

I like sentry guns and believe there is a place for them in a friendly narrative type of game. For something more competitive I'd go with Aggressors, with the caveat that they perform better in a group of 4-6 (I prefer 5).