Should I take a travel pack or backpack on my round-the-world trip?

One of the down sides to this job is that people expect me to advise them on how to have the most possible fun—i.e., how to travel the world, kayak in Fiji, ski in Aspen, and so on. That depresses the Gear Guy, who would like to travel the world, kayak in Fiji, ski in Aspen, etc., but is too busy answering questions to make such plans. I suggest that anyone reading this column send a $100 bill to The Gear Guy Fun Fund, care of this web site, so that I too can have fun.

But I digress. What you’re basically after is a pack with 4,000 to 5,000 cubic inches of capacity, as anything larger might run afoul of carry-on limitations, while anything smaller wouldn’t be of much use. Otherwise, the big question is whether to get a purpose-built travel pack or a “regular" backpack that can be easily retrofitted for travel use.

On the travel pack front, one reliable choice is the Eagle Creek Ultimate Explorer LT ($265; www.eaglecreek.com). It’s a large pack—up to 5,400 cubic inches, with the detachable daypack—that has travel-friendly features such as stow-away straps and a separate compartment for dirty or wet laundry. You won’t find the suspension to be spectacular for long days lugging a heavy load, but it’s fine for short hikes and getting around town. And it has an integrated pack cover/rain shield that doubles as a standalone duffel if need be.

One downside is that the Ultimate Explorer actually is a bit larger than most airlines’ carry-on limits. But you can get around that by detaching the daypack, which would then give you a piece of hand luggage plus a carry-on. Or, leave the daypack home.

I also like the Osprey Waypoint 80 ($259; www.ospreytravelpacks.com). It’s a touch smaller than the Eagle Creek pack, but with 4,900 cubic inches and a detachable daypack, it still offers plenty of carrying capacity. It’s also a little sleeker than the Ultimate Explorer, and its suspension shows Osprey’s backpacking roots and handles heavy loads with a bit more aplomb. It lacks a pack cover and is not waterproof, but some inexpensive plastic garbage bags or an after-market pack cover (such as Gregory’s Seam Sealed Rain Cover, $25; www.gregorypacks.com) will work fine.

Water is the main hazard to a pack and, therefore, to your gear. Otherwise, the Eagle Creek and Osprey are both made of tough, modern materials that ought to hold up to your adventure. As for what can prevent you from looking like a tourist…well, the minute you don a large pack you’ve pretty well made yourself as obvious as a pine tree in a wheat field.

The other option is to buy a standard backpacking pack. You’re apt to get a little more comfortable pack here, as the suspension will be superior to the fold-away models on travel packs. On the down side, you won’t have handy (well, supposedly handy) passport pockets. And you’ll need a light duffel to toss the pack into when checking as baggage. But it’s still a good option. Gregory’s Baltoro ($269) is an excellent mid-sized pack (about 4,300 cubic inches) that packs well and is exceedingly comfortable to carry. Outdoor Products’ Large Cordura Duffel ($25; www.outdoorproducts.com) will easily hold it, and the duffel’s urethane coating will keep it dry in all but the wettest conditions.

So there you go. Bon voyage, vayo con Dios, blah, blah, blah.

And I’d settle for $50 bills.

Get more advice from the Gear Guy as he picks this season’s top gifts in Away.com’s Holiday Gift Guide. You’ll probably find a few things to put on your own wish list, too.