I haven't ran the RB WS7II but they are a great motor. I dont have any complaints about the VZB tho. Killer low end power n revs through the roof. All these motors are gonna be comparable in speed. The difference comes down to your set up and gearing. I will say this, the OS gets over 9mins in a buggy which is definitly a key to help win races by cutting out a pit or 2. Bottom line tho, whatever motor you buy 1st will probably be your favorite cuz both motors are killer motors.

Have fun