IIRC:
+ Sacred Edge combos are easier to do(knocks up higher) and stronger (because all 2d's don't prorate)
+Greed Sever has better reach. Active time A LOT longer. You could get it to have frame advantages on wake-up.
+ Can Shin Akuma earlier(i think).
- HS VT has a longer active time, but techable (no VTL!)
- 2H doesn't vaccuum.
Overall #R Ky>XX Ky. You're gonna want to stock up tension on SE combos, 'cause that's where most of your damage is gonna come from.