The BYD Seal 6 DM-i is the Chinese manufacturer's entrant to the mainstream plug-in hybrid car market, available in both saloon and estate (Touring) body styles. With pricing starting around £35,000 and an electric range of up to 65 miles, this fresh Chinese contender undercuts established rivals by a considerable margin. However, while the Seal 6 DM-i offers impressive value on paper, it is still a way behind its rivals in certain key areas.