They will do better under led but probably still lose some. HID lights get super hot so it cooks them because there attracted to the light. I’ve only released them once inside and was using hps back then, so I can’t say for certain they won’t get cooked by led though.
I have however released them many times outdoors and they work well. They will eat anything that fits in there mouth, but aphids are what there good for.The best thing you can do is get them as early in the season as possible. If you can get them to reproduce, the larva eat 5x as much as an adult and there super fast. You cannot buy larva they have to hatch naturally.