For example, the telepathy crystal found in the Upper Tower, used to contact Eddie, comes from LGNPC Tel Uvirith, as does the slave in the upper tower and the new dialogue for your retainers in the homes outside Tel Uvirith. Rise of House Telvanni deals with most political Telvanni aspects, such as any interaction with Duke Dren.
Altogether, the content in BuUL and Uvirith’s Legacy exceeds what’s available in Building up Uvirith’s Grave alone, so it’s definitely worth it. Also, BuUL is more compatible with LGNPC Tel Uvirith, and doesn't have the same issues with Fast Eddie that BuUG did.[_/su_spoiler]