Hi Mark,
do consider the Cliffhanger.
These have only recently been brought to my attention but it appears Co-motion have adapted them for some of their builds where they once used the Chukker (I think).
They are mentioned on a couple of recent threads and you can easily find them on the Velocity site.
If I have issues with my Dyads (fingers crossed I wont), I'll look seriously at both the Chukker and the Cliffhanger.