I just switched from TitlePac to Title Program Administrators out of Phoenix.  Nancy Walker has been doing E&O since 1992 and really understands the industry.  Her quote was about 7% lower than TitlePac.
An important thing to concider when switching carriers is exposure to prior claims.  If you have any knowledge of a potential claim, it will not be covered when you change carriers.  If you have any fear that something you have already done may turn into a claim, changing carriers to save a few dollars is not a good idea.
I have carried E&O for 27 years.  During that time several underwriters have come and gone.  They come into the business with low rates, and realize after a year or two that they have underpriced the market.
I would caution everyone to be careful about changing their carrier.  E&O is claims made insurance.  It does not work in the same manner as your auto or homeowners policy.