Keis, stay away from anything but 16/44 unless you have access to high quality sample rate conversion/bit reduction equipment.
Your link between iTunes and portable/mid-fi devices is erroneous. It is very easy to distinguish between analog to digital conversion processes using iTunes. Unless you've used an iTunes like system, you cannot imagine the magnitude of the increased accessibility to your music collection. After switching to an iTunes system the end result is that I listen to more of my music collection than ever before. Now that's my definition of a good hardware upgrade.
Your link between iTunes and portable/mid-fi devices is erroneous. It is very easy to distinguish between analog to digital conversion processes using iTunes. Unless you've used an iTunes like system, you cannot imagine the magnitude of the increased accessibility to your music collection. After switching to an iTunes system the end result is that I listen to more of my music collection than ever before. Now that's my definition of a good hardware upgrade.