Have you checked the insurance companies ratings on the J.D. Power & Associates ratings?
http://www.jdpower.com/consumer-ratings/insurance/index.htm. That, and family recommendations, is how I picked my insurance company many years ago. Have kept them for 15 years now and had no surprises from them at all. In fact, no rate increases for a very long time now. But I keep reading about those who jump around between different companies end up getting big rate jumps. I'll just stay with my little, unknown, company as they have treated me well!