The subject of rear brakes for Felt tri bikes has been talked about a few times here. Searching through previous posts I see that that the Shimano 7800 DA, Zero G, and the Oval A700 brakes will work on the back. SuperDave also pm-ed me and said that the TRP 950 model is fairly narrow. Does anyone have any insight as to what the narrowest brakes would be? I am running a Shimano 6700 compact crank and I have about 2 mm of clearance between the brake arm and the crank. While the stock brakes work fine, I would like some extra space if at all possible. So in order from narrowest to widest how would these brakes rank?

1. Zero G
2. Shimano DA 7800
3. TRP 950
4. TRP 920
5. Oval A700
6. Bontrager Speed Limit

Brakes that don't work don't need to be mentioned. Just looking for the narrowest brake options. Any others I should be looking at? Also, do the Zero G's really perform as poorly as I have been reading about? "A" race next year is IMWI so stopping power is not something I want to give up :). Looking for the best combination of narrow + acceptable performance. Thanks!