Dave/Aidan,
The Trend N.Compass is a pretty new one in their range, but I did look at it in its original guise a fair while back when I got hold of one from the inventor, a rather clever bloke called Toby Cardew.
His company, M-Power specialise in inventing neat devices to make life easier, a lot of which are now in the Trend range, including the MiniMach,
M3 Square, TriScribes and Point2Point.
If you are having trouble getting hold of the Trend version (it is available, but the webpage and catalogue haven't been updated) give M-Power a call and they should be able to help. 01980 629526
They have a website m-powertools.com[url] which shows the full range of stuff they do.
Andy