Ergonomics would be the deciding factor for me. (Shattered knuckles on the right hand make this a very important factor, given I ride on the hoods about 85% of the time.) They are all excellent products, and as others have pointed out, there are group sets less expensive that will work as well. Because of the ergonomic factor I use Dura Ace on my Ti bike and Ultegra SL on my other road bikes. I switched to the Dura Ace 7900 chain on the Ti bike and it has been remarkable in how well it shifts, how quiet it is and has been holding up over the miles. As the other chain wear and need replacement they will get the 7900 too.