For most of us the pro isn't really a bump up. The pro is definately the way to go if you're running mod but for anyone running a spec motor (17.5/13.5/10.5) the RS is more than enough even in hot weather.
The difference in cost between the regular RS and the pro will put enough money back in your pocket to get a set of premounts, or a new rotor. It just about pays for a new motor and cuts a big chunk out of the cost of a LiPo pack. Hopefully the motors will be available soon maybe I can run all Tekin stuff in 12th this year.
I've been super happy with my RS running it in sedan. I can't wait to get back racing 12th indoors because this thing is so light. Might not have a car that's 2 ounces over weight this year.