Power-link, light weight, price, works very well with other Sram/Truvativ components
Some people complain they break, but I haven't noticed the problem
I've noticed the Sram chains available in Europe are made in Portugal. These I've noticed are better than their similar Asian cousins, that are made in China. I've noticed that with a mostly Sram (rear derailleur and cassette) drive-train are really slick but that Shimano chains jump around a fair bit, so better to stick with the same manufacturer here as the rest of your drive-train. Power-link rocks and is easy to use and better than KMC missing links.