One of the set ups I've been practicing is out of a combo I do. The standard Collider combo to a power spark bounce, and jump throw, you can buffer the 720 just as you would an empty jump after the throw assuming they don't tech out of the air throw. I'm not sure how reliable it is, I've only done it twice because I just thought about buffering it from there since that's the end of the combo, but it's definitely flashy as hell.
EDIT: After doing tests now that I'm home, they can completely avoid the 720 IF they tech roll behind you, or just do not recover and stay down, so most likely you're not going to get this move off if you try to use it all the time.
