I've got one of those and have used it. The device is beautifully made (perhaps a bit too complex - but nice CNC machining) and it works fine. When I was a boy we had a thing that looked just like a nut-cracker with an o-ring for tension and it worked well too. The whole idea is to relieve right hand cramps - and it works for me.
The cam lock looks like a well-designed, durable solution, but it is pricey. I use the Vista Cruise Control throttle lock which costs about $20. However, it does require some modifications to work properly on the ST1300.http://www.madcorider.com/cam-lock_honda_cruisers.html
I have used this one on nearly every bike I have owned in the last 10 years. Works great and very durable.