i will download these in a bit. i am just now seeing this thread too.
i can usually tell them apart pretty easily on my car system (usually its because of the bass, which on shit bitrate files, to me at least, seem like it was attenuated). ive actually caught some of my files that i thought were crappy quality (bit rate wise), checked them when i got home, and sure enough, they were the much lower bitrate files, which i had missed on excluding.
but even then, im gonna agree with vehementSPL. to me at least, unless its a super low bit rate song, the only time i notice a difference isnt even in the sound quality, but just rather, the output isnt quite the same. as far as quality, they sound petty much the same to me.
only reason i download 320CBR and v0 files is because id rather not risk any loss of output, that i seem to have experienced in the past.