So it's been about 3 and a half months since I first introduced myself and my new Marvelight.
I wear the watch basically everyday except in the evenings. It goes everywhere with me, running, working out, hiking, climbing, working in the machine shop, and it hasn't skipped a beat.
However, after observing it for about a month and a half, it was keeping about +5-6 seconds a day. Now, I know a lot of people would be completely happy with that and I thought I would be too but I couldn't shake the fact that after a month it would be almost 3 minutes fast. No big deal I'm sure but the urge to do better would soon override the desire to keep the case seal intact and unopened.
So I cracked the sucker open with a homemade 3D printed tool and gave the adjustment screw about half a click towards the slow side. Gave the seal a little silicone lube and closed it back up.
I wore it for 2 days continuously and it kept time spot on. Observations over the past month shows that it now averages +0.8 seconds fast a day.
The stainless steel bracelet was starting to get heavy and unwieldy so I replaced it with a Hirsch Carbon black strap. It's supposedly leather woven in a carbon fiber like pattern with white stitching and a rubber lining. I've jogged with it and the sweat seems to have 0 effect on it. So far so good!