It's a beautiful thing.
My hiking buddy Evan put together a nice 35-mile overnighter this weekend (well, he said it was 35 miles, but what's an additional five miles between friends?). Mostly rolling terrain, but a number of steep ascents and descents, especially on the second day. It was a chance to try out some new gear I've gotten. What made for an interesting gear choice weekend: Temps were around 30 degrees, or a bit less, when I started out Saturday morning, stayed around 30-35 throughout Saturday and Saturday night, around 30 Sunday morning, but quickly increasing to around the mid 50s by late morning/early Sunday afternoon. I put together three pieces I'd never used before, and one I had, to see how they'd do.
They did fantastic!
So, my base layer was a RAB MeCo 120 LS shirt (which I've worn before, even use it cycling, I love this shirt. It was the only piece of clothing, except for my Ex Officio boxer briefs, I had worn before), mid layer was a RAB Boreas pullover, and outer was a Haglofs Shield pullover. Pants were Paramo Cascada trousers.
I gotta tell you, the Cascada trousers are exceptionally impressive. They're not light by a long shot, but they work fabulously over a wide range of temps. I usually sweat buckets, especially trying to keep up with Evan and always when there's a lot of climbing involved. But these trousers breathed wonderfully. My briefs got damp, but never soaked, even on the second day when temps warmed significantly. Side venting zippers helped with that. They also kept me comfortable from the chilly beginning of the hike throughout the first day and night. In fact, I never took them off, slept in them as well.
The combo I used on top also worked exceptionally well on this hike. I was occasionally warm, rarely chilly (except at rest stops, I should have brought a down jacket to stay warm during brief respites during the day), most often comfortably cool - which meant never soaked with sweat, not even on my back, another first.
I wore all three throughout the first day and overnight (slept in them, everything was dry when I went to bed). Started out with all three on day two, removed the Shield after the first climb, removed the Boreas pullover 3/4 of the way through the second day. Again, nothing was soaked - my base was damp at the end of the hike.
I've never had a clothing system that worked so well on a trip. It's great to have a system dialed in for cool/cold weather hiking. Finally! Unfortunately, I've still got a bunch of new stuff to try!