Well.....I confess...I actually don't have any merino for my legs! :eek:
DH has several nice merino chamois shorts and also long merino tights. They are cool.
But I do have several good cold weather tights of various lycra/poly/windproof/fuzzy persuasion, including two with chamois that I like, and an UnderArmour coldweather base layer tight too.
My legs are staying warm enough with either one pair long tights and wool skiing knee socks, or else with two pairs long tights (one with chamois). My legs seem to be the last thing to get cold when it's 35-45 degrees out biking. It's my other parts I have to layer up more carefully, it seems.
What about you?