Hi Geoff, I know of a v low hours (30 ish?) 150 Optimax with (IIRC) 2 or 3 years warraty left on it....
I had looked at it, but am sorted with another now....
It was a few weeks ago, and may have sold, but if of interest I'd be happy to pass on the owners details (if I can find them) etc....drop me a PM if any use....
Dan