who is the best hardside luggage dealer?

It actually depends what you're looking for. Many online dealers offer incentives to buy with them. With some its price, and some the choice of luggage makers and styles of luggage. That being said, http://www.Luggageonline.com is a good option. They have a wide variety of luggage to choose from and consumers who have reviewed the luggage to help you make an informed decision.

My favorite luggage site is Ebags and here is an example of the great deals you can find there.  Traveler's Choice 3-piece hard-shell luggage set:

• 28" Upright: 28" x 21.5" x 12", 13.5 pounds

• 24" Upright: 24" x 17.5" x 11", 12.5 pounds

• 20" Rolling Upright: 20" x 15" x 9", 9.5 pounds

• Lightweight durable Polycarbonate ABS shell material for strength and providing maximum impact resistance

• The Polycarbonate allows the shell to absorb impact by 'flexing' when under heavy stress

Luggage Pro is another great site and here is a Samsonite Favorite you might want to check out.  http://www.Luggage.com is my last recommendation they also have a great selection of hard-shell luggage.  Happy Travels!