To me it is the system with which I use to compare other or new things. If I am looking to buy a new component for this system, my second system, for a vacation home, or to recommend to a friend or relative, I (at least in my own mind), compare it to my 'reference system', where it I have the best I have assembled. It does not imply it is better than any one else's system at all.
If one said 'my best system' would this be less off putting?