I think the Champion Suits should be sellable.
However, I'd put:
- high royalties on it
- make it account bound for 1 year
- make it visible when inspecting the gear of another player that the suit was earned by player XYZ (so people know who payed for it and who owned it prior to them)
Suits that have been owned by well know Champions will be crazy valuable.
Imagine getting the Michael Jordans jersey. Everyone knows that it's not yours, but it's still fire to own it.