If I've got this right (super theory fighter 4

), the mix-up from that thing is SERIOUSLY nasty any way you look at it. Consider Ryu's options after Zangief scores a knockdown and jumps on him during wake-up: Ryu can either a) shoryuken, his best anti-air option because it can't be safe-jumped and it potentially leads to Ultra, b) backdash to avoid incoming attack/empty jump SPD, c) assume empty jump SPD and jump out, or d) do nothing and get ready to block incoming attack.
A, B and C can all be air-to-air ultra'd. D is what happens after you've been conditioned NOT to do A, B or C, and then you're gonna get empty jump-in -> SPD or j.FP into tick-SPD guessing games OR, on connect, BnB into EX green hand knockdown and you go into the vortex. That's a ridiculous 50/50 to have to deal with on a pretty common situation.
SSF4 Ryu might be able to use Ultra2 as anti-anti-anti-air, but I dunno how fast it comes out. That'd probably work so long as it does the "catch" and doesn't immediately go airborne.