2009 17" Macbook Pro here. It's been on 24/7 every single day since it was brand new. Never flickered, never skipped a beat. I use iTunes for importing and management and flick Audivarna+ on when I want to play DSD or high res. USB output to Mytek Brooklyn. It couldn't be any simpler, put the sleep app on it and you can use it with the screen closed- like a headless pc. The HD is getting rattle after all these years so it's time for a new one, 1TB SSD.
Kuzma Stabi/S 12", (LP12-bastard) DC motor and optical tacho psu, Benz LP, Paradise (phonostage). MB-Pro, Brooklyn dac and psu, Bruno Putzeys balanced pre, mod86p dual mono amps, Yamaha NS1000m