(Bloomberg) -- South Korean automakers Kia Motors Corp. and Hyundai Motor Co. tightened their grip on the lead in U.S. new-vehicle quality with Kia ranked best in J.D. Power’s annual survey, the first time in 27 years a non-premium brand held the top spot.

General Motors Co. had seven winners in vehicle categories, the most of any company in the Initial Quality Study, released Wednesday, and the Detroit Three automakers’ domestic brands scored better on average than their import counterparts for just the second time in the survey’s 30 years. Kia’s rate of 83 problems reported per 100 vehicles in the first 90 days of ownership was one fewer than Porsche, with Hyundai third at 92.

“Over the last 10 years, Hyundai and Kia kept moving up, up, up, up,” Renee Stephens, J.D. Power’s vice president of U.S. automotive quality, said in an interview. “Quality has just been a priority in everything they do. It’s been pervasive, it’s been a journey, they never let up and that’s what it took.”

Survey used to make purchase decisions

The survey is an automotive bellwether that consumers follow closely and use to make purchase decisions. Industrywide, new-vehicle quality improved 6% from 2015, the biggest increase in seven years as 21 of 33 brands rated gained ground. Technology such as dashboard information systems remains a “pain point,” though automakers are making progress at addressing that, Stephens said. Korean and U.S. companies improved the most in making technology easier to use.