In reply to Oujmik:
I've had a Rab Cirrus for a few years, and have worn it for pretty much all my walking and climbing in that time. It's not indestructible, but it's stood up to some fairly consistent gritstone-based abuse and the fabric is just beginning to look tatty.
Breathability hasn't been an issue. It's also got decent pockets, which I'd say are incredibly valuable in a top like this because they can hold a pair of gloves and a hat and let you regulate your temperature without having to stop and dig in your pack.