Initial thoughts are that the FLAC version of the Pristine Audio doesn't add much but there are noticeable level differences the K2 version is much louder.
Indeed my initial thoughts were that PA version was maybe more relaxed sounding.
What is interesting through headphones-Grado SR125 than the PA version has noticeably less background noise than the K2 version-as Phasecorrect points out earlier the recording is quite hot but interestingly enough you don't hear the background noise when the disc is coming through my speakers.
I'd need to hear the PA version more but it seems lacking in presence and presentation in comparison to the K2.