IMO bar bags suck! Yes, they're convenient but that's the end of their good points. On the other hand, bar bags:
1. make it difficult to draft closely behind people as you cannot see your wheel
2. make it hard to avoid holes as you cannot see your wheel
3. get in the way of most headlights
4. prevent top mounted brake levers being used
5. obstruct STI cables unless these are unnaturally long
6. make carrying the bike up stairs or hillsides more annoying
7. are a magnet for thieves as they're easy to remove and typically filled with expen$ive stuff
8. make handling worse if there's any significant weight in them, and the longer your stem, the worse it gets
If you really want to ditch the jacket, there's a better way: Rivendell sell a couple of small front racks to which things can be bungeed:
http://www.rivbike.com/products/list/bags_and_racks (3 pages)
Admittedly, being made by Nitto, these are not cheap. Riv also have bags to fit them - some have D-rings for attaching clothes, i.e.,
http://www.rivbike.com/products/list...product=20-127. Also, some of the typical bar bag problems are reduced when they're off the bars, plus the racks give somewhere to fit lights too.
Wallingford probably have something from Gilles Berthoud that'll do the same job:
www.wallbike.com