Wavex was developed initially to reduce vibration in tennis racquets to prevent tennis elbow. They produced a Wavex range of racquets, which never caught on, and have since sunk without trace. The 'waves' were designed into the throat of the racquet, and possibly into the handle. There appears no support on the forums that it really worked in tennis. Indeed, the biggest factor shown to improve tennis elbow is grip size. So, there may be other artefacts causing the apparent improvement rather than the concept of vibration waves being disrupted (and even returned) by change in cross section.
The wavex website is down, and their Canadian stock value appears to be zero. May have gone out of business?
Do the Kippax handles have the standard springs in, or have these been dispensed with because of the 'wave' design?
Also, if the 'science' stood up, there would be a better explanation of how it works on the website. It looks like it was written by someone with a poor grasp of physics, or being deliberately vague . For a start they are not sure whether it is friction or vibration that travels up the bat. Be very sceptical of this handle until someone can provide an independent test.