+1

Website says 1,650 ci = 27 L. So they are slightly larger then Ortlieb Front Rollers @25L, and much smaller than Back Rollers @ 40 L.

These would be a good choice for a short chainstay bike due to the bag shape. You might have to combine with front panniers for adequate capacity, or simply pack lighter. They are not likely to be waterproof, so either rain covers or internal plastic bagging would be necessary for rainy travel.

Bushwhacker Moab bags can't be too bad a deal at $55 shipped.

http://www.bushwhackerbags.com/panniers.html

http://www.ortlieb.de/_pdf_en/radtasche_en.pdf

Here's the backside of another Bushwhacker model, looks pretty good to me.