We have an Rb S72 We have had it for 1 1/2 years, I just finally took it apart last week for the first time to replace the rod. It has approx 3 gallons through it, it ran away wide open so I'm replacing the rod early for extra insurance. We have raced agianst the C6 and the Ws73, in my opinion you dont need to spend the extra cash and the more modded motors may be harder to tune.
My son uses the S72 in his Jammin 1/8 scale, in his Jammin truggy we are running a Novarossi (Top) T21nb, Awesome motor for the $175.00 (
www.amainhobbies.com) He hasn't lost a race yet except for breakage, he loves this motor for the money, says it has almost as much as the Rb.
Rex