I dont do porting, just putting that out there.
I dont have any conection to the shop i recommend besides him being a friend.
On that note, yes CNC porting is good. My buddy wants to buy a 5 axis CNC but on the high dollar jobs hand porting will win. (In my opinion)
The CNC is only as good as the program and that program aint written to allow for core shift and other variables.
The CNC will hog out the port but the magic happens with a skilled person running a tool.
Just my opinion.