They've changed a little during the past few years. I remember going in there when I was in year 8. It was dark, the music was giving me a headache, and there was nothing that covered you up properly.
Now they have some decent stuff, although it's not really my style, casual clothes like singlets and t-shirts (non-slogan ones) are pretty cheap. The good thing about Supre is they have really small sizes. When I shop at Myer, most things are too big, especially pants.
The staff all look like skanks, but who cares, you're there to buy clothes.