Even though it's summer I'm looking ahead for commuting in the winter - my commute is short, only 3.2 miles, but the weather around here can get pretty wild and the distance isn't long enough to really get warmed up. It doesn't get too far below freezing in the winter, but lots of precipitation in various degrees of solidity. I've been looking for good insulated, hi viz cycling jackets but haven't found any. Last year I made do with layering under my Sugoi windbreaker, but it wasn't always adequate, and since the windbreaker was purchased to be a fairly trim fit I can't get too much stuff under it.

I've purchased some t-shirts and tech shirts from alertshirt.com and am happy with them, and was wondering if anyone has experience with their insulated jackets? Would they be suitable for riding a more upright bike? How well insulated are they?