IMO, DRS has more than 98% accuracy. And that is the maximum we can expect. When was the last time, we heard someone complaining about any of the DRS decisions? I know about only 2-3 cases, out of thousands of matches. So it is very rare.
BTW, the latest news from ICC is that they have already identified the winner of media rights auction. A total of 4 bidders took part in the process - Sony, Viacom, Disney Star and Zee. ICC has announced that the difference between the top bid and the second placed one is more than 10% and therefore no second round bidding will take place. The identity of the winner will be revealed by today (Saturday).
Technology is finding his way to every sport, even in Football we are seeing the review system. Last time we saw Kohli complaining about DRS against SA in test series and that was a bit controversial. Other then that everyone seems to be ok with this DRS technology.