The HotDO Hand Cannon is by far the best add-on to the Wii I've bought. After the extreme disapointment of the Wii Zapper, with its awkward grip and reliance on a nunchuck in the handle, I was about ready to give up on good guns for the Wii.
The Hand Cannon is the most perfect arcade rail-shooter addon for ANY system i've had. Well balance grip means that the remote isn't overly top-heavy in your hand, sites for those important boss fights and perhaps the most important factor...real arcade action feel.
This is perfect for anyone who plays "the House of the Dead" games, but is also great with "Resident Evil: The Umbrella Chronicles" "Ghost Squad" and is acually marginally better than the zapper on "link's crossbox training"