I already have the Manual of the Planes for 3rd edition. I also own the entire 30 book collection of Planescape 2nd edition. Well in any case I am getting ready (again) to run my first Planescape campaign this fall I was wondering which of the two supplements would give me better supplements for the characters particuarly in character creation but also considering other extras.
I wanted a little hand on expanding the number of races the players can choose from being that they will be adventuring on the planes. I hear many of the races in Player's guide to the planes were reproduced from Savage Species. In any case which if I had to choose would be best to pick up first. Also any other good 3.0 or 3.5 supplements that might help my planescape game out. (I already own 3.0 PHB, DM, Monster, book of vile darkness, deities and demigods, and the manual of the planes.)
Savage Species - it's got plenty of good races and the rules on how to make more of them - wherease the Planes book has a handful of species - some ok, some... crud. And a lot of stuff that's neigh unuseable or simply stupid in the context of a Planescape game (Like the last 30 some pages).
I'm not entirely sure I trust the Savage Species rules on race creation - but they're decent enough - and if I recall there's some good feats for winged critters in there. As always when homebrewing - feel free to bend the rules to make the race match better and not be over or under powered.
As for other books: Beyond Countless Doorways
(Yeah - it might not be canon PS - but it's still, from what I understand *very* good inspirational material for a planar campaign.)