Don't know if 6700 came with a triple. If not, you could go with a 6600 long cage derailler. Or better yet, follow your sense of aesthetics and get Sram. It's good stuff. Reliable, light and good looking. I doubt that there's any difference in the function and build quality between Apex and Force/Rival RDs. Just a few extra grams. All together it'll still be much lighter than Shimano.