[QUOTE 5120298, member: 45"]Cube Hyde Race ordered, arriving Monday.[/QUOTE]
Sounds like a good choice for your requirements.
Did you establish how the belt is tensioned?
The bike doesn't appear to have sliding dropouts, but it does have Thun's Zumba bottom bracket.
This is good because Thun designed it to work with the belt, which is particularly picky in terms of line.
Zumba doesn't appear to be eccentric, so there is presumably some other way of adjusting belt tension.
Or perhaps the thinking is that as the belt cannot stretch, no adjustment is needed after it's been installed at the factory.
I've never had a belt, but have not heard the few belt bike owners I've spoken to say it needs adjustment.
https://thun.de/project/zumba/