Useful for getting more specific ideas about what to populate my party's planar adventures with. I wish there were fewer "refer to this other table" statements in some of these tables, though - this led to a lot of time-consuming hunting around.
Must-have supplement for any DM who plans to run planar campaign or just considers taking his players to the Planes. I found these tables to be very helpful in my preparations.
Very well thought supplement, encounters are well contextualized and the level tables partition make this supplement perfect for each tier. Personally, I really appreciate the random location tables.