So I am considering trying out Dreamscarred's Psionics stuff (I never played 3.x so I don't have any experience with the original). Aside from using the rules on d20pfsrd, if I was going to get the actual books/PDFs, which ones should I get to avoid redundancy? What other products does Ultimate Psionics include and what does it not?
Currently I believe Ultimate Psionics includes everything except the Psionics Augmented: Wilder, Bestiary, and Embodied.
I have the hardcover on my shelf and love everything in it.
Also D20pfsrd doesn't have a lot of feats, archetypes, powers, ect from the Psionics line. I believe it's missing material from the Psionics Augmented Line.
Let me try to break it down a bit easier:
Ultimate Psionics: Contains everything in Psionics Expanded, everything in Psionics Augmented: Volume I, and everything except the monsters from Psionics Unleashed.
Psionic Bestiary has the monsters from Psionics Unleashed, plus dozens of additional new monsters that aren't found in any of the other books.
Psionics Embodied is a stand-alone book with 21 psionic NPCs. None of its content is found in any other books (it references material in Ultimate Psionics, since it's mostly stat blocks).
And as Andreas mentioned, Psionics Unleashed is getting a revised edition with updated artwork and layout, fully-implemented 0th-level powers (the original version didn't have them), plus the two psionic races from Psionics Augmented: Volume I. We expect to have it out in the next month in softcover and hardcover.
So will the revised Psionics Unleashed have things that aren't in Ultimate?
Only the small set of monsters it's always had. :)
As a player, everything you need is in Ultimate Psionics. Only a GM needs the Bestiary and Psionics Embodied. All three are highly recommended in such a case.
I can't say enough how much I love Ultimate Psionics. The powers are diverse and the classes great fun to play and GM for.