FF6 was my favorite. It has better gameplay and storyline than FF7, which was probably because of Square's emphasis on graphics. I really liked the story of FF8, but the gameplay is broken.

Simply put, after the SNES era was over, I wanted more out of my RPG gameplay. FF10 was not bad, but FF12 just sucked. I own the game, but stopped playing it half-way through. It is just another "healfest" and you would think Square Enix would be able to match the gameplay of Baldur's Gate but they haven't.

-----Amazing------
1) *VI*
2) IX
3) IV
4) XII
-----Really Good------
5) VIII
6) V
7) VII
----Alright-------
8) II
9) X
10) I
----Bad-------
11) III

FF6
than maybe FF4 on DS, FF7 on PS

Final Fantasy X

Then Final Fantasy Tactics

VII.

Well, I am going to say Final Fantasy X.

QFT!

FFVI FTW!!!!

I've stated that I like FF7 the best, but I also like FFX. I felt that the battle system was poor man's Grandia combat system, but it was offset by a very nice upgrade system.

I also liked FF12. Initially, I hated it. But configuring the gambit system was very deep. And in the end, I found the combat in FF12 faster than the previous outings. Character development was poor, though. Vaan's conflict was resolved way early into the game, and was more like a decoration most of the game. Balthier, a Han Solo ripoff, was almost the main hero.

FFVII

I wasn't implying that popularity precluded greatness in the least.  But it sounded like he was saying it was the best because it had the most sales. 

And I wasn't trying to "appeal to authority".  I only named twesterm because he commented earlier in this thread.  I mentioned naznatips because he usually (including in this case IIRC) has respected and well-supported opinions that he can (and has) backed up with good arguments. 

Everyone is entitled to his own opinion.  But I don't think the opinion I was responding to was well-supported, which hurts it when comparing it to others.