I really like what Blizzard is doing with Challenge Modes.
Any time they implement a new feature, they have to find a suitable reward to make people want to play with that feature. The Challenge Mode rewards are very creative. Finishing with a Bronze gets you a title. Finishing with Silver gets you a mount, and finishing with Gold gets gear.
The gear that you get has no stats, so you don’t use them as part of the gearing-up process. They are strictly cosmetic and used to transmog your existing gear. The pieces have interesting visual procs that go off during combat. This makes them very desirable because they are attention-grabbing, but they do not disrupt game balance.
Here is a video. You’ll see two procs – one from the dragon shoulders, and a smoke effect during combat.
Very cool! Blizzard thinks that gold will be hard to get, so if you manage to obtain that gear you will really stand out from the crowd.