To be fair, Pzfier and Moderna's mRNA vaccines seems to have greater efficacy (>90%) compared to China's vaccine, which is a traditional vaccine based on an inactivated virus (~80% effective). The mRNA vaccines also take less time to produce.
With that said, Chinese vaccine is easier to transport and store since they don't require significant refrigeration. Pzfier vaccine requires -70C storage while Moderna's need -50C. Sinovac's vaccine only needs about -10C I think for long term storage, and as little as 8C for temporary transport. Also, China's vaccine produce slightly less adverse effect compared to mRNA vaccines.
In short, China's vaccine is more suitable for developing countries that do not have the transportation and storage infrastructure for distribution.