Also, I should mention that these comments are based on my riding up to 3 hous in these temps. Through 2 hours I'm ok. Beyond that things start to go south.
I think you should try some of the Gore road gloves, but I can't speak for anything much over 1.5 or 2 hours... I seems to always have problems with my thumbs being cold.
Assos has a glove system that is mucho bucks that consist of a liner, glove and shell for 175! (wtf!) You can buy the 3 peices sperately too. Maybe mate your current gloves with the lobstershell? Again, 65.00 for a shell is steep but is it worth it for warm hands?
http://www.competitivecyclist.com/r...-assos-lobstershell-851-gloves-3591.12.1.html