I swear by both the carbon and the BD flick-locks. I was given a pair of Leki's with their version and immediately found them lacking: they wouldn't stay locked when I leaned down to step from boulders, causing the poles to collapse.
The flick-locks are also a must if you are in snow of ANY sort. The twisting style does not stay locked at all, especially with snow baskets.
I've already bent more than a few aluminum poles to make me never go back.
-L