Although I think my X5 actually sounded even better. (I always thought the violin and viola were a bit tinny, but the cello was fantastic, and the bass not too bad. And the choir sounded better in the lower register than that recording, though you'd still never mistake it for a real choir.)
I also recall the Day of the Tentacle theme desperately needed a good clarinet sound to sound really good. I often though the theme must have been composed on the 05/W that the X5 had the same sound set as, because it sounded that good. Alas, no Youtube love here. (Closest is the MT-32 recording, http://www.youtube.com/watch?v=YQeQzeVmN5w , but that is way worse than the X5 rendering.)
Fellow Korg X5 owner here (in fact, mine is still in perfect working order, sat underneath my bed).
It was an amazing little machine, especially for the money - I had great fun programming the user sound banks to do some Jean Michelle Jarre(ish) pieces.
But a fun bonus was hooking it up to video games that supported putting out music in General MIDI.
In an era where everybody was listening to Adlib FM on their Tie Fighter: https://www.youtube.com/watch?v=puvD_FDS_jE
I was listening to something more like this: https://www.youtube.com/watch?v=Ajz-m0qIDCk
Although I think my X5 actually sounded even better. (I always thought the violin and viola were a bit tinny, but the cello was fantastic, and the bass not too bad. And the choir sounded better in the lower register than that recording, though you'd still never mistake it for a real choir.)
I also recall the Day of the Tentacle theme desperately needed a good clarinet sound to sound really good. I often though the theme must have been composed on the 05/W that the X5 had the same sound set as, because it sounded that good. Alas, no Youtube love here. (Closest is the MT-32 recording, http://www.youtube.com/watch?v=YQeQzeVmN5w , but that is way worse than the X5 rendering.)