i think remastering of 95 and 08 will be very differenet, major imporovements. but from 01version i couldnt imagine a major difference
nope, they have exactly the same quality
(HIStory disc 1 has the same audio quality as the SE's do have
and the SE's have the same audio quality as Thriler 25 does have
EVERY CD release by Epic/Sony of a MJ album/single has had perfect quality since 1995
the rare "Signature Series" was actually the first CD ever by MJ to feature digitally remastered versions,
and as every Epic/Sony CD-release (not J5/TJ) since HIStory has been digitally mastered, there's no need to remaster them. their sound is already perfect
for further understanding you should first know, what digitally remastering actually is and when there's need to apply it at all,
the music industry knows that people who are not that common to such techniques would buy sth when it's marketed as "digitally remastered" although it has always been digitally mastered - thus having NO difference in sound quality at all)
but as not every fan has the SE's or HIStory, they probably won't know that the songs have already been remastered for ages.