Just seen this and it’d fix my problem with using an edge 800 on the standard mount on MTB bars which always make me nervous. Should I just whack a standard SRAM mount on there like I have on my road bikes but back to front or is this actually better?

the Barfly 3 MTB mount is way shorter and works with short MTB stems down to 50mm as it lifts the Garmin up higher than the SRAM. the SRAM one is much longer too and mounting it backwards with short stems puts it behind the steerer tube, which is worse i thing than out front as you are likely to knee it at some point. you would be ok if you run a 100mm plus stem on your mtb though.

I have both, use the SRAM on the road bike and the Barfly on the MTB, prefer the barfly and would recommend it to anyone.

If your 800 does landscape mode then you could consider the 1.1 also.

However this will not solve your worries I would imagine, although it will bring it neater in for you perhaps.

The 3.0 will be the best for you probably.