I have a pretty fancy stereo system that I bought when I really didn't have enough money to afford such things, and I do like it, but I feel like any quality difference that I hear when I'm playing lossless audio is largely psychosomatic. An mp3 or AAC with a high bit rate sounds pretty damn good, so it's fine for nearly anything.

All that being said, I still use FLAC for nearly everything for two reasons: 1) Since it's lossless, it makes a good "transit medium"; I can have some assurances that it's not going to degrade in quality with subsequent renders if I import the audio into a video editor and export it to 24 Bit FLAC.

2) Hard drive space is pretty cheap nowadays. I have a home streaming server that I set up to stream to my stereo (doesn't do any additional compression from the input source), and even if it is psychosomatic, I do like knowing that I have the highest quality possible. I'll admit it's silly, but the music sounds better psychologically because I know it's lossless, even if I realistically cannot tell a difference in a blind test.