Compared with China and Russia, the US vaccines are very well tested and reported for safety and efficacy.
For instance, the trial by AstraZeneca was immediately suspended becos of just 1 case of side effects. Even though it has now been resumed in all other sites, the trial is still suspended in US as FDA demand more data from AZ before it is allowed to continue.
The other by Pfizer and Moderna also reported and explained the drug side effects and urged to monitor closely , eveb though only 5 patients have the effects and are very mild (headache,chilled) and the participants quickly recover after 1 days.
Because of these thorough and transparent investigations, one can feel safer and better using US vaccines aa compared to Russia or China vaccine.