In reply to Hat Dude:
Throwing an alternative into the mix I recently got a pair of Mammut Serenity's. Partly the increased thickness for not a great increase in mass over the Mammut Genesis/Beal Cobra while being possible to use as a single for lower grade routes where you may be moving together and taking coils. They're also fully dry treated so are ideal for winter mixed stuff where ice lines are a bit skinny and easily damaged on cairngorm granite.
I did have concerns over longevity when compared to the Genesis but I had a good chat with the guys at Dicks down in Bristol who suggested that their experience was that both seemed to wear as well as each other. Sure, there is definitely extra weight to be carried compared to a lighter (and thinner) rope but I just can't see it affecting my grades while the increased thickness gives additional safety margin. For that additional margin I'm happy to carry the extra weight.