This Luggage Guide will provide you with the advantages and disadvantages of different types. One particular piece is not necessarily right for every trip.
With airlines tightening their restrictions on the weight and size of both checked and carry on luggage, lighter is better.
Suitcases
What should you look for?
Weight of the suitcase when it is empty. The lighter the better but don't sacrifice durability and other essential features.
Cordura or ballistic nylon fabric. It's more durable than polyester.
Check out suitcases with wheels that can be pulled in any direction.These suitcase are more maneuverable and less likely to tip.
Look for wheels that are attached with screws. Recessed inline wheels with ball bearings are usually the best and quietest.
Make sure the zippers are durable and easy to pull. Chain zippers (fused to the fabric) are better than coil zippers (sewn in).
Look for handles on the top, side, and bottom. These will help you lift the suitcase.
Backpacks
What to look for:
A waist strap and padded shoulder straps. These will make carrying the backpack more comfortable.
Weight. Backpacks should be very light when empty.
Cordura or ballistic nylon fabric. It's more durable than polyester.
Water resistance. Either a water resistant inner liner or a rain cover.
Carry-on
What to look for:
Look for the relevant things listed above under Suitcases.
Also check the dimensions of the suitcase or tote. Most American airlines have the same rules for carry on suitcase size (as a rule, length, width, and height total 45 inches)
Generally a 21" or 22" inch suitcase will meet these restrictions.
Carry on size may be further restricted on smaller aircraft like MD-88, Boeing 737s or regional jets.
Some European airlines, especially the budget airlines have much stricter weight and size restrictions for both carry on and checked baggage.
If you will be checking your primary suitcase, you can use a laptop case, a wheeled tote, a backpack, a large purse, or anything else that meets your needs as your carry on.
Remember if your flight is really crowded, you may have to check your carry on luggage also. Have a small tote or backpack available so you can transfer your valuables and essential items. This rarely happens on a transatlantic flight but could happen on a connecting flight.