Having played to about week 115 or so in the Final Imperial Push GC as Hand, I think I've gotten a pretty good feel for how the change to Damage_Airspeeder has affected them. As of now, in terms of effectiveness, I feel like they sit somewhere inbetween the T-47 and the V-Wing. They're roughly as fast as T-47s, with a similarly sized hitbox, but they have a considerable edge over them and the V-Wings in sheer stopping power. That being said, the V-Wing is still a dick, since it's so fast, and has a hitbox that the aiming AI in this game really do not like. So, basically, the Air Straeker kills faster than either of them, but is more vulnerable than the V-Wing due to its lower speed and not irritatingly shaped hitbox.
I have found this to be a pretty good spot for them, they're still very useful, and fill out the Hand's unit roster nicely, and with the change I think they might actually be one of the most balanced units on the Hand roster. They're strong, but they have a notable weakness, and they don't tend to do very well in a prolonged engagement, anti-air units or no. I've had them slowly whittled away by everything from AT-STs to 2-Ms, so I don't feel like I'm even coming close to cheating when I use them, like I usually still do when I use Gilzeans, or especially when I use a squad or two of Gilzeans in combo with an MMT, or like I invariably do when I use the XR-85 droid tank, which I think will be my next target for balancing.