What 12TO just posted. Most people expect brand loyalty to be rewarded somehow, however a lot of companies these days exploit it in a counterintuitive fashion, basically their line of reasoning goes something like "hey this fool bought our last spiel, let's see what else we can get away with this time around". Meanwhile the best offers go to potential new clients to entice them into the process. The old trick of rotating through providers is getting neutered as well, as they build up databases, offers get 'customized' so unless you subvert their system you won't even know what's being offered to someone else, in effect the pricing has become opaque to the consumer.
Used to have USAA insurance, and they were hands down the lowest price for good vehicle insurance. However early in the 00's their home coverage rates became very uncompetitive (they had huge hurricane losses to recuperate), so switched to Allstate. Also discovered then that in a number of states, these insurance companies access your credit history, which could lead to a much higher premium.
Whatever company you go with, be sure to incorporate adequate uninsured/underinsured motorist coverage into your policy. Nothing like being involved in an accident that is some deadbeat's fault who isn't covered.