I have the Northface duffle a in every size. Yeah, I love them. Used them for the past 8 years or so. Traveled all over the place with them (hunting, fishing trips, intl trips). Carried the XL through Morocco and Egypt. Pretty much bomb proof and very water resistant. As others mentioned, fabric is waterproof but seams aren't sealed and zippers are't waterproof. The bigger ones have shoulder straps like a backpack, which is handy if you need to carry it for any distance. It gets marked up from abuse, but it can take a beating. I also bought the XL roller version. Called "rolling thunder" or something like that. Very sturdy, but damn it was heavy. I would go over the airline weight maximum before it was even close to being full. I used for a trip to Belize and BC for fishing trips. I really like having some rollers though. Sold that bag. I couple of us did a lot of research comparing bags with rollers. Even bought a bunch only to return them. We settled on LLBean rolling duffles. Not as durable fabric as Northface, but strong nylon fabric, good low profile frame and very very light. Gave up very little weight for the convenience of wheels. Size is XL. That's my go-to bag for traveling now, unless I need to bring my bow. Probably used it on 3-4 trips now. Held up great with one small rip from the airline. Can't beat the price and LLBeans 100% guarantee.
If I'm bringing my bow then a use a giant nylon duffle bag I bought online. REI's duffles weren't big enough. This one I would probably fitinside. The one I bought I put my bow case, boots, clothes, etc all in the bag. I pack my small clothes in the bow case with the bow. The big items go around the outside of the case, but still in the duffle bag offering protection. If I need organization, the REI sells these super light weight zipper pouches in the travel section. Use those and weigh almost nothing. Literally. Worked really well so far. Never been over the weight limit.
Pay attention to the weight of bags. Less compartments are better...means less fabric and zippers, equals less weight for the bag and more weight can be used towards your stuff. It's pretty easy to hit that 50lbs limit.