Oh man, some of the posts here sound like they are just choosing which name they like best...no offense. The WiiKey is definatly most superior in features. It unlocks multiregion and the "key" to it is you can update/upgrade it via a dvd-r disc. This is so important because you never know if they will still work after the next system update, but with this feature you can stay one step ahead.
Heres another big problem with the Cyclowiz-it can ONLY be used with the Wiis released at launch, not the second batch (with the good wrist straps). This is because the chipset made by Panasonic has already been updated and is no longer compatible with the Cyclowiz