As far as I know, it doesn't alter the content in any way (unless you alter the built-in EQ or dithering is switched on), so this is incorrect. Way back I tried programs that try to enhance the music and they clearly distort the music. I had a problem with my computer once, years ago, where the treble had some harshness which turned out to be the result of iTunes Sound Enhancer somehow having been switched on.
Well if it doesn't alter the content in any way... then there isn't any difference between it and any other bitperfect player. Unless it's the only bitperfect player that isn't totally full of errors. But this is a technology that's been mastered for a very long while so I doubt that.
There's plenty of DSP effects that sound quite swell. I even like using Dolby Headphone every once and a while on certain recordings, it actually appears to let more detail come through in certain areas and sounds pretty cool on songs that mess around with positional cues and whatnot.