Personally, I get fitted whenever I change equipment.  There can be changes to our swing over time and I think it it best to get fitted again to ensure a proper fit for your new equipment.  As an example, two years ago when I was fit for my 712 AP2s with the Fittingworks Tour Van, I was fit with a standard lie.  When I was recently fit with the Fittingworks Tour Van for the 714 AP2s we went 1 degree flat.  Same individual was fitting me both times but with different results two years apart.  This year, when we looked at the data with my current setup, my miss was consistently left (which was generally the same miss I had on the course as well).  With the setup change, the ball flight was straight on.