There appears to be a handful of CD releases for Once Upon a Time in the West, but I’m assuming that the best release is probably one of the GDM ones. There were three releases under the GDM label, but as far as I can tell they all appear to be the same with them even featuring the same catalog number (GDM 2062.) The only intimidate difference that I notice is the packaging, the first one (released in 2005) was a digipak, the second and third (both released in 2006) had jewel cases, but the third one featured a different cover from the other two.
There was also a 50th anniversary release in 2018 by Beat Records, but it looks like the only special thing about that release is that it contained an extra track featuring some harmonica sound tests.
Either way, I prefer jewel cases over digipaks so I’m considering one of the 2006 releases. I think I may prefer the cover art used for the third CD as it’s the same artwork from the theatrical poster. Regardless, if there are any other releases of this soundtrack that you think are comparable or superior to that of the GDM ones then please let me know.
As for The Great Silence there are 4 CD releases, 3 of which were by Beat Records and one by a Japanese label, Seven Seas. As far as I can tell, the 2005 & 2011 CDs appear to be the same as the one released in 1995, the only noticeable difference being the cover art is slightly different on each one. It might be worth noting that he 2011 release has a different catalog number than the other two (CDCR 126 instead of CDCR 27.) Other than those three there’s only the previously mentioned release by Seven Seas from 1995. That one features a different cover as well and also excludes the bonus tracks from the film “That Splendid November” (Un Bellissimo Novembre) which were featured on all three of the CD by Beat Records.
I’m not familiar with either of these two labels so I’m not sure if one is more likely to have produced a better CD release over the other, right now I’m thinking I might just go with the initial CD release by Beat Records.