Didi has option for both Taxi and private car drivers, you want a better car there are several options in the Ap. I went from using taxi to the private cars and found them 100% reliable, better car, better driver and more often than not cheaper too.
With some bad press in China with the private car options they responded and have several new security measures and I can vouch I feel safer in a China Didi hailed private car then Uber US car.