So having lost one edge 200 via an o ring failure and departure on the current mounts, I have been using an old zip tie 301 mount and to be fair its ok but like the K edge out front mount that I also have, I don't like the position as I really would like it over the stem. If you have a long enough stem then the K Edge can be mounted upside down which will put it over the stem but not if your running a 50mm this is also the case for the new Sram MTB mounts.
So I contacted Martyn at http://www.racewaredirect.co.uk
and he provided me with exactly what I was after. A 3D printed stem cap Garmin mount. It's now been in use for about a fortnight and has survived a couple of tumbles (front wheel wash outs in the dust!)so it's fairly robust, weighs very little, mounts where I wanted it on a 50mm stem and so far hasn't fell off. So big up to Martyn who I have no association with by the way and Racewaredirect. Highly recommended.
[img] image by Outlanderimaging, on Flickr[/img]