Eh, I wouldn't go so far to say it's amazing yet. The 2nd hit is unsafe, how much has yet to be confirmed. And given the gap between the two hits, quite possibly also stepable on block, and it doesn't look like it's hit-confirmable.
But yeah... it'll definitely have a place in his toolset, if only for the fact that you could always just B if you want to play more conservatively with it. I'll take it.
As for a:B. Its speed hasn't yet been confirmed. Strife 6B was i19-20 if I recall correctly. It does look faster as a:B, but how much is uncertain. Here's hoping they made it i16. I doubt it's faster than that though (B6 and B should have the same speed unless they changed it from past games).
Btw
@IceColdEdge
Can you confirm that 66B has no stance transition? I'm asking because Night's 22_88B goes into NLS now, apparently with excellent block frames.