Lo0ve the Kerrits. I don't like their "sit tight and warm" becasue they are SO sticky! But the older knee patch ones are super! I don't need long johns under them but I would add that if I lived in your climate!
IF you have the money, Tropical Rider makes awesome deerskin winter riding breeches. Pricey , but will last forever!
Agree on the Kerrits. I love, love, love them and just smile when everyone asks why I'm not shivering along with them. They keep me plenty warm.
I am short (5'3") and I have a real problem with their lengths. They don't seem to make "short" in any of their pants, at least not that I can find, so for my everyday stuff I have to buy the "regular" length riding tights and pull them up past my belly button so they don't bunch around my ankles. Not very fashionable, but warmth is the priority at this point in the year! It seems that every manufacturer has "long" options, but no short!!