I put together the best system I've ever had, including dedicated circuits in my listening room, about 6 years ago, which was when I was about 30 years into this hobby. The speakers (Genesis 500), amp (ARC VT100 MkIII), turntable (Linn), and CD player (Marantz SACD-1) remain unchanged since that time. I changed the ARC LS-15 preamp to the BAT VK30SE about 2 years ago. I got a vintage Mac 67 tuner about 2 years ago too. I think this system will stay with me until I get too old and arthritic to bend over to turn everything on and off.
BUT--I have two other systems (living room with ARC tube integrated, ProAc 1SC monitors, and Ayre CX-7 CD player; and bedroom with HT setup--Aragon and Acurus, and ATC monitors) that I experiment with and change cables, etc. It's silly, I know, and when it comes time to move it will take me months to disconnect and box up all my equipment and CDs and LPs, but trying new things is all a part of this hobby. At least I leave my main system alone. I don't want to mess up a good thing, which is easily done if you read reviews and classified ads, which I unfortunately do.
