I’ve been to SXSW twice and have attended the opening dinner both times, and from my experience you get an amazing dinner but thats about it.  If you’re an industry person you get a chance to mingle with other industry types at your table.  I had usually a music agent and an artist at my table when i ate so one from Austraila and the other Norway so the conversations were interesting but at the same time the Music fest is kicking off so u might sacrafice a band or 2 by attending.  Hope this helps!