I use the Rivendell Sackville Lare and it is huge which I like. I can load it up with tones of stuff and it does not seem to effect the handling like a pannier would because the weight is being carried closer to the bikes center of gravity, me. My Sackville Large and a small front basket is all I need for three season touring. When I go touring in the winter I usually trade the front basket for two panniers and am good to go. I like it a lot incase you cant tell. Yes, its expensive. Yes, its rugged. Yes, I think it looks good doing what it does, and yes, I would buy it again.

-Nun the OP lives in the States and I dont think that he can get a Carradice as cheap as a Zimbale. I have been to the Zimbale store here in South Korea and it is also a pretty small operation. Very nice people too if you ask me. The quality of the bags is also very good. You can get the 18 Liter Bag from Sheldon Brown for $130.

http://sheldonbrown.com/harris/bags/zimbale.html

Here is mine Sackville, also in Korea with some burial mounds behind it: