I bought a pair of these after really digging the Atom short sleeve jersey. I would class these as XC shorts, mostly because they are very lightweight. Not necessarily fragile, but they are thinner than my Fox Sergeant shorts, which have been my current favorites. I am mostly an AM rider, but I do roll XC and commute by bike about 35 miles a day on workdays.
These are lighter and cooler than the Sergeants, although the Sergeants are light and cool enough for me and they are more brush-resistant and sturdy. When I drop my phone in the thigh pocket on these, it moves around a bit and I can feel it through the fabric, whereas the Sergeants hold my phone more firmly and I can't feel it the same way. These have a zipper on the thigh pocket, though, which is more secure than the velcro on the Fox shorts.
These are also longer than any of my other shorts, so be prepared for that look. They fit true to size, I wear a 34 in these and my other shorts. These are loose enough for comfort and movement, but they don't get caught on the seat or anything.
All said, I like these shorts and they see as much action as the Sergeants. When I went to order another pair of shorts last week, I went with another pair of these.
Fall is here and although I'm not as concerned about heat, I just like these better right now, paired with an Atom jersey. But that could change tomorrow...