Well, you can't hear the difference on crappy speakers or on headphones in the subway, no. But pop it on a good loud-ish soundsystem with a decent soundcard & I guarantee you you'll be able to spot the difference.
Lossless 'breaths' more, it has a wider soundstage & the bass is more together. Also you won't get as much ear-fatigue from lossless.
A tune with lots of complex harmonics, brass or high hats, usually sounds pretty bad in mp3. 320k or even 192k on simpler tunes is OK but lossless is better all the time.
But coming back to beatport, I have started to buy my house on Bandcamp, same tunes as Beatport but only $1 for lossless, goes strait to the artist & if you buy the whole release its only a couple more $ for the vinyl + Flac.
Gotta love that.
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