I thought this thread was about "your best Sega music", not "your best Sega album of all times"... -_-
By the way, I have not one single best music from Sega, yet. Since I like much more the bosses themes than vocals or stages, this one is probably the best music Sega have had ever made on their life:
[youtube:34lnl8jw]hgTYHZnXkuc[/youtube:34lnl8jw]
The music's name is "Profound Darkness", composed by IPPO, who has left Sega after a long time right after Phantasy Star 4 had finished.