I rented game 3 a long time ago. I hated it. Who makes a game with that franchise that hard? And it was the stupid kind of hard, too.
I played game 4. It's not anywhere near as good as the main series games, but it's not terrible. The weirdest thing about it was the complete lack of randomness during battles. This meant that every battle with the same monster would play out exactly the same, accounting for your exact actions. This made it easy to figure out the best way to deal with each monster, but it also made the battles extremely boring.