I've been tuning this list for a while, and I really like the latest version. I just took it to a store championship and came in 2nd of 51. It's brutal against anything that the formation gets in its sights, and TIEs are pretty good (though not perfect) at making that happen.
Darth Vader + Crack Shot + TIE/x1 + Adv. Targeting Computer (31)
Zeta Leader + Crack Shot (21)
Howlrunner + Crack Shot (19)
Black Squadron Pilot + Crack Shot (15)
Wampa (14)
It has a lot of red dice to chew through low-agility targets, and against hard targets it has some bigger attacks (Vader and Zeta) plus lots of Crack Shot and (occasionally) Wampa. Howlrunner is also key in making the damage consistent.
It's a lot of fun to fly -- you can be aggressive and unafraid of jousting anything, and TIEs have good dials for when things get messy. The range of pilot skills and Vader's lack of 1 hard turns can be challenging, though. As a bonus, the formation looks quite good on the table (IMO). I have Howlrunner painted and Wampa in his blue, so all five TIEs are unique.