Chris Pakwrote a review of Mammut Genesis Dry Climbing Rope - 8.5mm on April 17, 2015
maybe I'm into 'old school,' or I'm paranoid, or maybe just weird, but I really like using half ropes. Sure, it's more of a hassle to manage, and can lead to some serious clusters if you don't pay attention, but I like being able to do full length rappels, split up the rope nicely for carrying, and being able to use these as twins/doubles whenever the situation arises.
These ropes in particular are great for rock - the most durable half ropes out there. this is definitely because they are also one of the fattest, but there is always a trade off. I'm happy mammut always adds a halfway mark - I don't always need to do a full length rappel.