Not having the 3.5 book, I can't say I've used it. If I do use it, I'll filter it.
I wasn't running games when just Eldritch Wizardry was out.
In 1e, the appendix served more as a munchkin option, and went by the wayside as our playstyles matured.
You missed one! When the psionicist class appeared as a class in the dragon, I used it more. It seemed a more solid archetype and less abusive since you couldn't have major powers at first level.
The 2e Complete Psionics was probably one of the more flavorful versions of the psionics combat system, be the cracks began to show with relatively low level characters having access to potent power, and the power gaming possiblities were gross.
2.5e S&P was broke as written. In psionic combat, you did more damage to yourself than your opponent! I house ruled the heck out of it and based some major groups in my game on it, but I still had problems in play with PC psions. During this era, I instituted my own version of the "transparency" rule by creating some overlap in mechanics like magic resistance, because I came to realize what a problem that was.
3e blew everything earlier out of the water, but still needed some nips and tucks. I guess that's fair, since 3e did too (alt.rangers, anyone?) The psionicist needed upgraded, and psionic combat was near worthless, and the displays, while a good idea, were a little overblown. I tweaked the class and a few feats.
If Thoughts Could Kill reaffirmed some of the changes I made in Psions, but I still had my own tweaks (frex: inner power, body fuel, and hide display feats.)
Mindscapes was a great addition to the game. It took psionic combat from something that was in the book that sounded interesting but nobody ever did, to something that became a regular and flavorful part of our game.
3.5e I don't have yet. So far it sounds promising (and it sounds as if it accomodated Mindscapes combat!), but it sounds like it will be a headache to adapt, and it sounds as if the "new core class mania" that brought us MinisHB and Complete Warrior has infected this book as well.