SpaceX successfully completed their test flight last month.
In comments, people are saying the Crewed Dragon didn't fly with a full working environmental control system, and that problems took place in the Dragon - ISS hook-up, by my memory in the area of computer interfacing.
I don't have time to look up the authoritative reports on those potential problems, but it's fair to say that SpaceX isn't perfect either, but looks to be leading this race. The common point of failure is NASA.