I’m a fan of versatility when it comes to gear bags and the luggage I use when I travel to fish. Lately, I have been testing a few models from Clear Creek Fishing Gear, and my favorite to date is the Still River Kit Bag ($119). It’s 2160 cubic inches (18″ wide, 10″ deep, 12″ high), which makes it a reasonable size for a carry-on or an overnight bag for a weekend trip or, of course, a gear bag that you can toss in your vehicle or on a boat.
The exterior fabric is rugged and water-repellent (though not waterproof), so I’d trust checking it through on a flight, but wouldn’t leave it exposed to a rainstorm.
I especially like the dividers (which can be manipulated/removed) and the exterior pockets with simple zippers. I also like the bright interior, so as I pack and unpack, I’m sure not to leave things (like flies or tools) in the bottom of the bag when I’m ready to fish. The shoulder strap is comfortable, and the bag itself is light (though capable of hauling heavy gear).
It’s not overdone… just functional. And at that price, you get a lot of bag for your money.