Once I got moving this proved the perfect amount of layering, in fact eventually I took off the windbreaker only to have to put it back on on the downhills. You don't want to overdo the layering because you want to move, and even if it's cold you will sweat, and that sucks if you get all sweaty and then have to ride downhill in cold. Think "wind chill" on your sweaty body.
I think it's the toasty headcover, finger covers and foot covers that keep me warm.
Here's a pic of my favorite cap, which you can also monogram! Sorry all that was available was this teensy image from Land's End.
