Does anyone else find the mirror parts tools difficult or impossible to get a simple mirror result?

The only options for Mirror Type are:

• Centre of bounding box
• Centre of mass
• Component origin

If I use any one of these options in mirroring multiple parts in an assembly,

the "mirror" is not a true mirror. The parts are displaced relative to each other

because each part's bounding box / centre of mass / origin, have nothing to do with the way they were positioned.

E.g. if I have 10 parts touching or centred on each other, when I mirror the components all together, 

every one of these Mirror Types messes up the mates / relative positions.

All I am trying to do is create a quick and dirty mirror as a visual representation

with a plane acting as an actual mirror, without creating new opposite hand parts (which loses the appearance properties).