Just finished it! It's my least favorite so far. All the others I've played (1, 2 and Oath in Felghana on Steam, and emulated 3 on TurboGrafx-16) had some difficult puzzles and boss fights, but this is the first one that made me check a guide for a puzzle (couldn't find an item, however much I searched for it). I didn't dislike it, but it's kinda weak at times. Bosses were repetitive, and despite having used a guide for the final two, they weren't as hard as the other games in the series (not complaining here, I get frustrated when they kick my ass repeatedly). The music was good, yes, but that's a constant within the series. I also don't like not being able to move diagonally, it makes combat harder than it should be.
I'd only recommend this game if you're a completionist and wanna play them all. Which is my case, since I'm going to play the TG-16 version of 4 afterwards (read that it's better than the SNES one, hope that's true!), and then 5 on SNES. Again, all of these emulated with a fan translation, because they aren't available in English otherwise. Only then will I be free to jump into the remaining PC games, which I've already bought, in this order: 6, Origin, 7, Celceta, and 8.