What is the test for admitting an expert opinion in a motor vehicle accident case?

"Neal did not involve opinions on the legal question of whether coverage existed (since coverage concededly was present in Neal ), but instead involved opinions on questions concerning such factual issues as the promptness of the insurer's response to settlement overtures. [Citation.] Opinions approving the admission of expert testimony as to factual matters such as industry standards for [69 Cal.App.4th 1181] dealing with covered claims cannot be read to authorize experts to opine in the first instance as to the existence of coverage." (Devin v. United Services Auto. Assn., supra, 6 Cal.App.4th at p. 1158, fn. 5, 8 Cal.Rptr.2d 263.)