switched from seat bag to panniers and rack
Am very glad i just made the switch. Not only can i carry more (two Ortlieb front rollers used on the back = 25L vs 14L of seat bag) I found the following benefits
- handling is better (no wag)
- weight is lower on the bike (which helps handling and making it seem less obvious you are carrying weight)
-I can hold more (and heavier) stuff - even hanging stuff on the bags and/or rack
-it is easier to get to my stuff and remove the bags from the bike (thanks to Ortlieb's excellent design)
-with an Axiom Streamliner Road, the aerodynamics don't seem to suffer much, if at all
- it looks better imho
- it is much more stable
If you are contemplating a seatbag or pannier/rack setup, I highly suggest the latter.