I'd be curious on design choices like waterproofing, battery life, things like that. Also I think you mentioned your site is getting worked on but pictures to clarify what it is about would help sell it.
The watch hardware is waterproof (but not submergeable), it works for 1 day without special optimizations (all-disabled-low-power-mode on original firmware about 2 months), it has a sunlight-readable display which should work with GPS for at least 6 hours without any optimizations. That's enough for a trip. It only has 8MiB storage space, but that should cover a couple hours worth of GPS track. It's the same device as used by Bangle.js 2.
The web site was put up before I started the firmware work, so obviously no pictures :) They will come once the project becomes more useful.
I will sell them together with a Bluetooth wheel/cadence sensor once I figure out Bluetooth.