@rvpiano states, "I'm really happy with my System"
What more is the Goal.
For me such a statement means the end sound I experience, as I don't do too much with the capturing of ones thoughts with a aesthetic. Function before Form is how my Audio Tools have evolved.
Additional to this, I have been demo'd numerous systems beyond my own, where a selection have been undoubtedly containing devices, I am certain would be beneficial to try out in my home system.
I have at present a short list of devices to achieve home system demo's off, with the intention to learn how these devices work to produce a alternate (not better/bettered end sound).
There is not a device out there that I sense can be brought home to be used, that will change the way I enjoy my system as it is at present or even in earlier guises.
Creating an alternate end sound, does not mean for myself the change heard is able to be more enjoyable, merely just a expansion on sonics I am exposed to, as result of the influence of a particular electronics selected for a device.
If one wants to part with $300 to experience different end sonics produced in their home system, I suggest the supplier of the alternate devices is encouraged to bring along more than one device only. At least the end experience will be a broader understanding than what just one device will do.
FWIW, it will usually take a longer period than a few hours of exposure to a different electronics device to fully realise the value of it being added into the Signal Path of a very familiar system.