I saw this a few weeks ago, and knowing my kids wanted to know what to buy me for Crimbo, I suggested it. It was allegedly used in MotoGP first ?
It just turned up this morning, and considering my luverly SD is hibernating for another couple of months, I won't be using it just yet. I've never owned a bike which has such a small amount of slack (7mm) needed in chain play. And as some of you have found out, it's better to go a tad greater, otherwise the torque through the chain can lead to those oval plates which lock your rear sprocket in place from flying orf WWW.tru-tension.com/chain-monkey

Hmmm, personally I don't think I'd want set of those on any of my bikes and I doubt they've ever been anywhere near a MotoGP bike - don't imagine that scrutineering would be too impressed.
But, if it floats your boat then press "buy now"

https://m.youtube.com/watch?v=5NiDFohUbYY
https://m.youtube.com/watch?v=5b9lB9pntaM

Can't imagine seeing it on the works Honda somehow