In reply to jay.mac:
I have some of the 3/4 tights which I use for skiing under Paramo salopettes - very happy user. If moving/working hard in them they keep you nice and cool, dries fast which is nice.
Got a long sleeve winter weight top too. Price-wise not that bad when compared to merino (maybe not so good against a standard tech tee...) but performs so much better. Definitely my go-to next-to-skin layer for everything winter.
I have no idea about running as I don't...
If I was looking for more next to skin layers and I could try some on I wouldn't hesitate.
If you can stand the drama and intensity of American television that's not a bad go at explaining how it works.