An audio component you just can't let go

“What makes this component so special?”

Any component regardless of price or brand that allows you to connect with music is worth keeping around. A component must possess Musicality and the Synergy with rest of your audio gear. If a specific audio component cannot convey music with its natural emotions, then it simply gotta go, IMHO.

right now it’s NOT my tv with the sound blasting election news for the 100th hour straight and I just want to shoot myself.

I have a few pieces in my system that qualify, except (as you specify in your post), I haven’t replaced them or removed them from my system.  Occasionally I take them in to have some of the internals upgraded or repaired, but they will always be an integral part of my system. 

So the pieces I can’t let go of are my musical instruments.  My string bass, my electric bass (which turned 50 two years ago), and a couple of my guitars.  I haven’t played them in over 35 years, but they were so prominent in my life that I’ll never sell them.

 If we speak of electronic component, my akg k340 and my Sansui amplifier  of the alpha series are irreplaceable in term of S.Q. /price ratio ...