I never found hitting the rare truffles to be that difficult. I usually do it in the final world, forget what it's called at the moment. There's a wide open area near one of the final save points where rare truffles spawn. You just have to get your timing down. Jump hit land. Jump hit land. Don't do huge jumps, just small ones. You want to jump because Sora will uppercut the truffle, sending it higher in the air and giving you more time. It takes rhythm. At first I tried doing it in Neverland but the controls there are awkward and I couldn't do it.
You forgot an optional boss in there, mb, was it on purpose? (SPOILER)Sephiroth was the hardest boss in the game for me, so hard that my brother didn't even believe I beat him. So I had to do it again to show him.
