Was wondering if a Marta/Marta SL with a 160 SL rotor in the rear has enough stopping power for a 200lb rider (w/gear)? Bike is a new Niner RIP9=30.5lbs with Kenda Nevegals and an I9 wheelset, Stan's rims=600g's.

I have them currently on my Air9 and performance is awesome. Just wondering what their like on a heavier bike. I will be using a 180 up front.
Any comments? Power, modulation?