Found Voyager Blitzwing and Springer in LA on Saturday.
One word-review: awesome.
Robot-modes for both are pretty dead-on. Blitzwing has a changing face. Yup. Only minor issue seemed like the robot mode for Blitzwing was a bit loose in the shoulder area, but maybe some things weren't pegged-in properly? Springer's feet are a bit odd out of the box, but he stands OK when you flip-out his back foot part.
Wheeled-Vehicle Modes: Both are excellent. Blitzwing's cannon has a 'slide the tube and the missile fires' feature, which I don't think we've seen before? Springer is really solid and has no helicopter kibble whatsoever.
Flight-Modes: solid again, but not as good as the wheeled modes, IMHO.
Both would rank a 9/10.
