Got all except the Katy Perry one (which I picked the 320kbs mp3), but I glossed through that one because, well, Katy Perry.
I listened on these - http://www.yuin-acoustic.com/product/?id=2
- plugged into the headphone jack of cheapo computer speakers, so no good amp really but decent buds (although they're pretty beat up at this point).
It's pretty easy once you know what artifacts to listen for. But honestly, 320kbs mp3's are pretty tight and if the mix is compressed to hell like that Coldplay, for example, anyone's going to be hard-pressed to notice a difference in casual listening. I don't care what kind of golden ear you claim to have.
I still love my SACD setup at home. There's certainly a case for higher-than-CD quality but, like this test shows, it only shows itself in certain places.