I have a couple bib tights. A Gore thermal that stops the wind, and a Bontrager for use when it's not too windy. Just bought the Bontragers and really like them. I've begun with temps as low as 36º, and as it warms up to mid-50s, they are not too hot.

A buddy of mine has bought a number of things from KB Cyclewerks. He likes his tights from there, and the price is really good. Don't know how long they will last.