Best seat bag???
 

I've done various forum searches on this one and I seem to be coming up empty. I already have a Specialized Dirt Bag that unzips to expand it's size with a maximum volume of 160 cubic inches. I like the bag, but just in case there is a comparable bag out there with similar volume I thought you folks might know about it. Most of the others I have seen have a smaller capacity.

Cannondale Fastbag 240 for me. attaches with velcro straps so no buckle necessary has a small zip pocket inside where I keep some money and can expand if necessary by unzipping the bottom.
http://www.performancebike.com/shop/...tegory_ID=2310

Kenal0

If you want something out of the ordinary, the Banana bag or Little Joe are nice. They look pretty good under that Brooks Saddle too...

http://www.rivendellbicycles.com/web...cks/20082.html

It's probably too small for your looking for but I really like the Specialized mini wedge. It tucks up very nicely under the saddle and holds all the essential things. It even has a separate side pocket for tire tools. It just seems like a lot of thought has gone into it.

Plus there are several colors to choose from!! They run around $15.

I've tried (and have) about 4 other models and that one wins hands down.

I use this bag from Nashbar. 717 cu in expands to 905. Moveable dividers in the main compartment plus a nice size compartment on each side and the rear. Attaches to rack with four velcro straps. Has a handle on the front so you can take it off and into the restaurant. Rainproof zippers, shoulder strap and a rain cover that pulls out from the bottom. Well thought out bag. I got it on sale not long ago for $24.00. The only complaint I have is the length is a little long and it overhangs the rack and can sag down over my tail light. A little home made extension on the rack will solve that problem.

http://www.nashbar.com/profile.cfm?c...eid=&pagename=

Carradice Barley or Pendle with the QR mount. I carry a first aid kit, Topeak Alien, Leatherman, patch kit, levers, spare tube, a couple of clif bars, lock, Road Morph pump, oil, grease, headlight, spare blinkie, jacket, wallet, keys, cell, smokes and lunch with room to spare in my Pendle. The Barley is just a little smaller. QR allows me to swap between bikes in seconds.

+1 for the Baggins banana bag. It holds a lot of stuff and looks great on a Brooks.