The RCA/Sony 2 CD editions of Star Wars sounds okay. It's a little dynamically compressed, but it's not too bad. The width of the soundfield is different; the original album tracks and the cues that appeared on the Arista box set had more discrete mixing. I used to like the sound on the 2 CD set better, but I'm finding as I get older, I tend to prefer the original mixes, which, while not technically accurate, was what the music was recorded and mixed to sound like.

The sound quality on the 2 CD sets of Empire and Jedi are a completely different story. They're awful, the Arista box set and the original PolyGram CDs had much superior sound.

Jedi sounds particularly bad on the RCA/Sony 2 CD set; it's completely lifeless and muddy. On the other hand, it does contain a lot more of the score than had ever been released.

The box set also had a few alternate takes from what appear on the 2 CD sets, and of course “Lapti Nek” and the album and film versions of “Ewok Celebration” from Jedi, but also the alternate “Leia Breaks the News” and the film version of the Empire end credits (bells are more prominent during Yoda's theme, Yoda's theme does not tail off over the beginning of the Imperial March).

The most confused state of affairs would be Empire, as there are a myriad of versions from the LP, Arista and Sony/RCA editions, many incorporating different takes or mixes. On the other hand, as has been pointed out, ABC and DJ have done most of the gut work already for that score, and their project could serve as a basis for a lossless sync.