I use Bar Mitts on my brifters.
+ They take up less room in the pannier than bulky gloves when the afternoon commute is much warmer than the morning (typical in TX)
+ They are easy to stick your hands into compared to putting on thick gloves/mitts
+ Very warm but if your hands get too hot, just bring one hand out to cool it off
+ Waterproof
+ Easier to work zippers, wipe nose, get things out of pockets, grasp water bottles, punch buttons on lights/computers

- Very limited hand positions and a little cozy. I'm OK since I ride on the hoods 99% of the time.
- Not elegant