I did leave my unit out on the porch yesterday afternoon...temps were in the high 20's F. The focusing did stiffen up slightly but no worse than many other bins I own. It is certainly smoother, even at the colder temps, than some of the porros I have on hand.
I do feel the need to again mention the amount of time that I have owned this bin...going on 4.5 months. It is looser, in regular room temps, than it was originally so I am left believing that regular use makes the focusing mechanism smoother in all temperatures. We are talking about a $200 binocular though so I don't expect it to offer the same type of cold weather performance as something like the Leicas with their lubeless design.