ATX6XX cars are not recommended, both in configuration and appearance are not as good as 7XX.
The transmission systems of these cars are all Japanese parts. If you don't like Japanese goods, please assemble them. ATX7 frame +SRAM X5 transmission system +SRAM9-speed flywheel +AVID BB5 mechanical disc brake +RST front fork+nine fish drum+rim. Pick any MAVIC, but the price is not low. Other common parts of the toothed plate can be removed by a car like Giant, about 2000 ~ 3000.
Personally, I think the parts of SRAM (especially the pads) are much better in appearance than those of Shimano in Japan, with good performance and cheap price.