I would hate to mesh a cage! It's frustrating when there are good big cages - except for the bar spacing. That 1m square rabbit cage is a find though Amityville. Loads of floorspace.
Actually Ferplast make a hamster version of that first one you linked. It's hard to get hold of and not cheap. And I'm not sure it would work as well as a conventional cage, because it's not as big. I thought about it for a holiday cage but decided a conventional cage with the bars and base nested was more space-saving. Plus it's not cheap.
Ferplast Deluxe cage criceti Small animals - Buy cages and parks online Miscota