Some time ago, years ago, I discovered Buffalo Systems and their pertex pile products- an all in one garment for the great outdoors.
Not waterproof, but shower resistant and breathable, lots of ventilation options, and a warm lining that wicks away sweat and keeps you dry and hicomfy. No more layering needed...
I like my Buffalo shirt, or is it a Special 6? but for most of the year it is too warm for me. It needs to be below 5C to contemplate taking it out. For the rest of the year I have a Teclite shirt - lighter weight and better for warmer days. Even that's pretty warm and has been useful for more vigorous activity in minus temperatures - its great for winter cycling for instance.
Much as I like both though they don't come out the cupboard as often as you'd think. They are not really lightweight by modern standards. In principle you can save on layers, but to take them on longer trips I'd still want a warm layer for stops and overnighting, and a waterproof layer in case of persistent heavy rain. Whenever I do the sums they don't make the packing list.
Today though we were out for a local ramble and it seemed a good chance to get reacquainted.
The weather was sunny but a blowy 5C. Feels like 1C said the app. Shame I didn't check that before hand.
Looking at the sunshine I picked the Teclite. Its cosy and comfortable on, but in company the pace was just a wee bit slow to counter the chill from the wind. OK at the beginning, but after an hour and a half I was glad to pull on another layer over lunch, and keep it there for the 45 minutes back to the car. (We had wind and hailstones on that stretch so it was pretty chilly!).
Conclusion... Still a good practical piece of gear, but if id realised how chilly it was I'd have taken the Buffalo shirt not the Teclite
Pros:
Comfy & easy to wear
Good storage with kangaroo and full width front pocket
Good ventilation and regulation - open the sides, adjust or push up the cuffs open the collar and even the pockets.
It does the job of a base layer, fleece and wind shirt
Limitations
It doesn't work out lighter than alternatives - they are designed for when you are active so you need a back up for stops..
The neck zip is a little short for best ventilation - a sacrifice of having the kangaroo pocket.
Great for wild trails, but not so stylish for stopping off at civilization on less wild trips.
But I do like it :)