They're really good if playing with random players who don't have the best 'battle awareness' (the kind a single infiltrator can get in the midst of and take down 3-4 of them with a knife before they realize). Stay with the spitfire, it'll alert you to enemies you might have missed, you spot and shoot them & your allies do the same. If you didn't have the spitfire up, that LA might have got your sundy, or picked off a few of you. If there's a stalemate in a base or a lot of action at a certain point, the place for the spitfire is guarding spots you can be flanked from. It's impressive how much damage a single engineer can do with sticky grenades & bandoleer if they flank and nobody notices them. Saying "I'll watch the door, you watch the stairs?" (the '?' shows respect when talking to a random who doesn't have to do anything you tell them) is nearly as good as a spitfire when guarding a room, sometimes better because a spitfire doesn't alert you fast enough if someone gets the drop on you. The health is in an ok place for a spitfire you can deploy more than once, making it stay up longer under fire from another player when you're repairing it with max repair tool would be nice. The damage is enough to get a kill assist or take down LA's eventually (can you use a medkit in midair? might solve some problems LA's have with the spitfire)) The size would almost work in your favor if you could crouch behind it and repair tank in a 1v1 situation. Being able to place it on slopes would be nice. It's been on live long enough to know it's nowhere near OP, it's safe to increase the carrying limit.