I've just bought a bike mount for my Satmap Active 10 and I'm a bit underwhelmed - the first time out on the trails the ratchet slackened off and after a couple of hours it was just flopping about on the handlebars.
However, I did notice the strange "Abus" logo on the mount - strange because Abus make locks and not GPSs. It turns out that Satmap seem to have saved a bit on the design by repurposing a type of mount that Abus use for their locks, no doubt to save on development costs. If you google for "abus under saddle klick fix" there is an alternative type of mount that may well fit to a generic RAM bracket -
http://www.cyclestore.co.uk/productDetails.asp?productID=10058.
Time for a little detective work.