I must say that I've never seen so much input or discussion on what is considered a "mid" layer. I'm still primarily a runner and as was mentioned earlier, I think cycling is somewhat behind other outdoor activities when it comes to cold weather clothing. I am using my closet full of cold weather running gear for cycling. I'm certainly not going to ignore all of my UA and Nike Pro Combat gear. I typically run in temps down to the 20's with no issues keeping my core warm. I put on a base layer short or long sleeve shirt then a long sleeve top. I really like my Pro Combat Hyper Warm tops and tights. Usually that's it for me, I'm a hot potato except for my hands and head. Extra care for these areas. I did just buy a new style UA top. It's winter weight, fitted fit, has thumb holes, 1/4 zip, and has a built in neck gaiter/hood/balaclava depending on how I wear it. Can't wait for some 20's next week!! Might even have to throw on my North Face running jacket to block the wind when riding. Maybe.