It is worthwhile stating that amongst audio engineers, it is widely accepted that Red Book CD (44/16) is
indistinguishable from any of the higher resolution formats in blind testing.
What often results in better sound with these releases is that the higher resolution versions have been remastered, which does indeed often make a difference (sometimes quite substantial). But the difference comes from the remastering, not from the extra bits.
You can test it yourself, try downloading the high-res and 44/16 versions of a track or tracks from hdtracks. Then use
Foobar to do blind testing. if you can't tell the difference, then you are saving yourself some money and storage space.