Whenever I switch doctors, I never had to bring in old medical records. Only specialists specifically request records, in my experience. Most PCP's don't have time to call the insurance company unless it is to verify coverage. If a doctor does want medical records, I just say that I haven't had insurance for years and have used the ER when necessary.
My old PCP basically ignored my chronic back pain for years. I know he thought I was a drug seeker, I couldn't even get anything when I was passing a kidney stone. So when I got a new job at a doctors office, I asked to be seen as an emergency patient, it was an actual emergency that time. Well, the doctor was so nice I made her my new PCP and when I told her about my pain and other symptoms she actually took me seriously and ran tests and finally dx'd me with fibro. She prescribed Narcotics and has never asked about previous docs. I guess it all depends on who you see. And I don't think that going around trying to find a doctor who will listen to you and treat you with respect is doctor shopping. Remember, they work for you!!

Sarah