I was wondering which skills these affected the most and before which skills it would be best to use it while in the middle of the rotation. At the moment Ive just been using it so I can get an extra skill in so I dont have to use a 0 energy filler, but Ive been playing around with it and found that I can put it anywhere in the rotation to get the energy benefit, so was wondering where is best.

Thanks for the replies

So for the most part, it's used for its energy, but there are ways to try and maximize it's usage when it is up.

Virulence: I always use it when there's a window to use 1 takedown and 3 lethal shots, and the previous filler window included dots. Normally you can't do that because of energy, but I use it right after I do that and before that next cull. I can then use takedown and SoS which benefit the most from the armor pen.

Engineering: It's pretty much solely used to fit another Orbital Strike into the rotation. Because the rotation is very strict and doesn't really allow for any variability, there isn't much else you can do. Depending on energy, you'd either replace a basic attack/roll with orbital, or a Vital Shot.

Marksman: Here's where you can do the most with it. The abilities that are the most important to fit in here are ambush and penetrating blasts. It also helps with energy usage here too. What I do is right before a sniper volley window, I line up my rotation so I can ambush, followthrough, penetration blasts, followthrough, sniper volley, penetrating blasts, followthrough. And then with the extra time I'll just finish it off with the snipes. This is also the only point in my rotation where I'd ever delay using a corrosive dart and use it after target acquired ended, otherwise I always keep it on the target 100%, with only the second snipe taking a higher priority (so I don't lose out on a followthrough).

Hope this helps.