American Gov is far, far more fickle and likely to "get involved" / abuse export controls / fuck over friendlies due to domestic politics. Space is ITAR heavy, there's less guarantee that private American company can honor agreement than CCP verbal contract. This is 2024, JP steel just happened, US "rule of law" means nothing when strategic interests involved, never have. Can't say the same about PRC, granted they're to high end capabilities export. Ultimately, going with PRC likely will get you ITAR tier tech access bundled with cheaper launch, see state of military drones sales.