Taking into consideration how keyboard steering is rather abrasive and sometimes dangerous, mouse steering should work for a better driving experience. Since console players have the benefit of using analog sticks for smooth steering input (and triggers for better acceleration/brake control, but that's a different story), I hate to think that PC players shouldn't have that sort of liberty.
So far I know that some games like GTAV and BeamNG.Drive make mouse steering work decently enough, although I'm not sure how it would work in DayZ's game engine.