Luggage

I am a huge fan of rolling duffel bags. I have a simple black cylinder shaped Pullman rolling duffel that has been all over the world (similar to the one seen here). It just has one long single zipper outside and a zippered pocket inside. I prefer the simple, single zippered bag. For me, all the extra pockets don't necessarily make for more storage, they only produce a more rigid, zipper strewn bag.
You want as much space as possible and all those various little pockets take up space and only create more places in which to lose things. Theft can be a real issue in some international airports and having one zipper makes locking up your bag much simpler. Also, other belts, clips and ties on the bag can cause problems on the baggage conveyor belts and can cost you extra time and money at the airport, having the bag wrapped in cellophane. I recommend sticking with the most simple, basic rolling duffel you can find. I have a similar duffel without wheels, but once full, it kills my shoulder and thus has rarely left the attic. They come in various lengths. I can, when in the fetal position, almost crawl inside mine and zip myself up. Not that I have tried it...
To find a bag, I recommend searching http://www.pricegrabber.com/ for rolling duffel bags. I have also seen basic ones in the luggage section of T.J. Maxx for $39.99. Mom and Dad got my Pullman, in perfect condition for $10 at a yardsale while in an upscale neighborhood in Whistler, B.C. The cost savings was well worth whatever Canadian germs I may have picked up, and I assume they all fell off somewhere underneath the pile of the other 300 bags on top of it somewhere over the Atlantic. It's not Louis Vuitton, but it really is the best way to go.

If compartmentalizing is an issue, try packing cubes or even Ziplock bags. I have a trio of these cubes made by Eagle Creek and they are very functional. I use them to separate undergarments and bathing suits while on my trip and for storing dirty laundry on the way back.

Also, every boring gently used black bag needs a fun and easily identifiable luggage tag. If you have ever had luggage lost you won't forget to mark legibly with your visiting address. I have these in pink.