Could someone really break down the differences of the 3 versions. Realistically I'm not gonna get the symphony version as it's too expensive (although I would like to know that irc is), but Amarra and Amarra HiFi are within my price range. I've demoed both and the only difference I can tell for my purposes is cache and playlist mode, neither of which I really use. But before I make my purchase I have a few questions. Is there a sound quality difference between the standard and HiFi versions? What benefit does playlist mode add? Is it worth paying extra for the standard version? I did a bunch of searching and just couldn't find clear answers to my questions. I hope someone can help! Thanks!