What materials do you use? Do you have any conversion rules?
We have about everything Wizards released and a looong shelf of 3rd party material. A lot of it gets used at one point of the other. We also had to convert our many custom races and magics to PF as 3 of the games are long time running and in homebrew settings, going as far back as 1999. The good thing is, some of the PF changes were already house rules in our D&D games.
My husband and one of the other players have a conversion system (which partly includes killing some of the benefits of a specific class/prestige class but dependent on who uses it) while I'm trying to keep the flavor of it straight. I'm not good with numbers and statistics (dyscalculia) but my husband and our Mr. Statistics are.
I do not always agree with them, but usually I can see why this or that was changed to keep the game balance. I think since PF was released there was only one PrC that was deemed unfeasible as it was designed to boost a fighter/mage combination in a way pointless to PF.
You've got a lot of faith in your players...
We have experience with them

I have yet to see anything really broken, with the exception of my son (new player at the time) not noticing that his destrezador (homebrew class) combined with some feats from a 3rd party book turned out overpowered. We noticed half way through the game.
The bad part? Before we can start any new game or have to replace a character, the discussions about how to make a single PC balanced can take time from gaming. But that was not that much different before PF. We kept our neighbors awake many a summer night sitting in the pool and discussing characters on weekends.
Oh yeah, I have one group where this wouldn't work, one I'm playing in, but we come together rarely, maybe 4 times a year, and haven't converted to PF.