Not sure what difference a CR9EKB plug would make. If I understand NGK's coding, this plug has (2) ground electrodes vs. (1) on the OEM plug.
The reason people are using the CR10EK plug is NOT because it has a double ground electrode. It's because it is one heat range colder than stock, which has been dyno proven to give like 2 HP increase over stock. I don't beleive NGK makes a CR10EB, or people would probably go that route for same benefit.