Tesla’s factory owned stores took the lead over traditional dealers in a Sierra Club study of retail stores selling plug-in electrified vehicles.

This spring, 174 Sierra Club volunteers visited or called 308 different dealers and Tesla stores across 10 states to conduct the study. The retail locations represented 13 automakers and are located in California and the nine other states following California’s zero emission vehicle mandate, where automakers are directed to increase PEV sales.

On a five-point rating scale, Tesla led with 90 percent of secret shoppers rating the experience as positive and 10 percent as mediocre. Number two on the list was BMW with over 70 percent having a positive experience, and over 20 percent rating it mediocre and about five percent rating it as a negative car shopping experience. Chevy, Nissan, and Audi took the next three spots and Audi finished last on the list.

Criticisms made by Tesla CEO Elon Musk during state-to-state legislative battles were reflected in the study findings. Musk has said that traditional dealers often have poorly trained staff selling PEVs, inventory is light, and show little interest in selling PEVs when higher sales commissions tend to come from large, gasoline-engine vehicles.

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In the study findings, about a third of the time, sales staff didn’t discuss federal tax and state rebate incentives for purchasing a PEV. When survey respondents asked to test drive a car, there were told at 14 percent of the dealerships that the car was not sufficiently charged, including at 22 percent of the Chevy dealerships and at 21 percent of the Ford dealerships visited. Only about half of the sales staff provided information on how to recharge the PEV while driving.

California set the pace among the 10 states in the Sierra Club study. The study volunteers found they were two-and-a-half times more likely to discover not even one PEV on a dealership lot in the nine other ZEV states than they experienced in California.

Another notable part of the study findings was a chart showing the percent of all U.S. sales made up of PEVs in the first six months of 2016. Beyond Tesla’s 100 percent, Porsche came in second with 4.95 percent sold and BMW finished third with 4.05 percent during the first half of this year, according to Wall Street Journal figures.

Gas 2.0