In reply to Shane jones:
I own and have used both ropes fairly extensively (all dry treated versions).
In short the triple-rated serenity is a compromise. In order for it to have single rope strength but be skinny enough to pass for a half-rope its sheath is thin and soft. Conversely the sheath on the genesis half ropes (having lower core strength requirements as they're only rated as halfs) is thicker and tougher and they are VERY durable.
My first serenity was an 80m for sport climbing, I think it lasted 4 or 5 trips before getting horribly worn and sketchy looking. My second serenity I've used as a dual duty half/single for a few weeks in the alps and its still going but getting fluffed up quick.
My pair of genesis I've used for loads of alpine, trad and winter since 2013 and they are incredibly tough. Getting very slightly fluffed now but more showing their age in a bit of stiffness.
IMHO the only reason to use the serenity is where weight is an absolute priority (and you need the option to use it as a single), because the durability is a big downside. If you're looking for workhorse half ropes that will last well and give you confidence then the genesis are excellent. If you get the dry treated version you can use them for anything.