Currently there are 2 ways to make a mirror part: geometry only or geometry with features. If you use geometry only, then the mirror part changes automatically when the original part changes but patterned holes are not recognized for patterning screws,etc in the mirror part. If you use geometry with features when making the mirror part then the patterned holes are recognized for patterning screws in the mirrored part but the mirror part will not update when you change the original part. This forces you to manually maintain both the original and the mirror part to make sure that they are always true mirrors of each other.
We would like to have the the mirrored part update automatically when the original part is changed but also have the ability to recognize patterns for placing screws, etc.