Testing done. Overall opinion of DV-188 v DV-988
Daytime footage: 988 is much cleaner. I think a bit of it is to do with the vibration of the bike but still think the picture is a lot cleaner. However, buildings are somewhat distant and much more fish-eyed than the 188. One thing I liked about the mobius camera was you can adjust the field of view.
Nightime footage: six of one and half a dozen of the other.
Audio: Hard to say. I haven't worked out how to mount the microphone where I want it without the wire looking tacky so it's still in the topbox, but I am guessing much of a muchness.
Timestamp: I don't like the blue of the 988 and it's a bit small compared to the white of the 188. It is much more clearer in the dark but I still think they should have stuck with white and larger font. The gps dots disappeared when I turned off the gps function.
Power: The 188 occasionally freezes on start up. I've never experienced this with the 988. Likewise the 188 didn't turn itself off which flattened the kwaka's battery one weekend. I have since disonnected the red cable to the bike and now use the usb one provided with a powerbank. If I forget to disconnect it I have a flat power bank but can still start the bike. This system is also good to let it run whilst inside shopping.
Battery: The 188 has an internal battery. When the power bank runs out it stops recording and turns itself off. The battery maintains the date and time settings. The 988 has no battery and a super capacitor instead. It can only hold the date and time settings for about 24 hours before resetting to the default (july 1st 2020 midday). Given I only use the xmax for shopping and it comes out once a week it means I have to either constantly reset the date and time. I bought a solar powered kit which I am hoping will overcome this problem.
Waterproof: Both cameras are water proof but only the 988 console is. Mine sit in the topbox so it's not an issue. Retrieving a memory card from the 988 is much more difficult and I have to carry a small tool or knife of some sort to get it to come out. Fortunately I shan't be changing it on road like I do the kwaka.
Filenames: I prefer the 188 version. The 988 version is helpful when dates and times stuff up though.
I think that's everything. If there's anything anyone wants to know feel free to ask.