I've played FF 1, 7, and 8. The first one was when I was in middle school and over the summer. For almost a week all I did was eat, sleep, go the meetings (what a waste!) and play that game until I beat it. I also beat 7 but it took me a little longer. I played 8 for a while but didn't get very far because I hated having to do those stupid card games to get stuff. If it weren't for that it would have been a great game. Does X have that in it? If not I may have to check it out sometime.
On a side note, I've been playing a lot of Gran Turismo 2 (don't have a PS2, yet, so I'm stuck playing PS1 games). Its a great driving game that's very realistic and takes forever to beat which, to me at least, is a good thing.