So here's a little bit of what the GoPro gauges look like:
It's not the most exciting footage ever and as you can see I'm not exactly setting the water on fire with my speed. In my defence the wind was quite light and I only rigged an 8.6 as I cbf rigging anything bigger. I'm also getting fat which doesn't help. My GW52 recorded a max 2 second of 22 knots and the GoPro seems to be pretty close to that. My original estimate of half a knot difference seems to be a bit harsh. It looks closer than that.
This was my first use of the Hero 5 gps and it worked first time which was kind of suprising. To get the gauges up in the video you have to use the quik app, the GoPro desktop software doesn't support it yet. I usually use Sony movie studio 13 platinum and there was a noticeable drop in video quality with the quik app but I've only used it once so maybe I can tweak some settings. The editing in the GoPro software feel a bit clunky compared to the sony program but it's free and the sony stuff is 100 bucks when it's not on sale so it's a bit unfair to be critical of the Go Pro software.
There are other gauges available but I disabled the less relevant ones to keep the clutter down. One of the gauges shows altitude which could be cool for kiters to make a jumping vid with real time height. I'm Going to try to get down to budgiewoi soon I'll post a budgie vid if I can manage it.