FE10 is the best for me. It's the longest, has some great characters, and has tons of characters (a huge plus). It also has the best music, and is one of the hardest.
FE9 is pretty good (playing it right now). It has a fairly dull start, and an obvious story. You see where you're going every time. Music isn't that good
FE8 has a good backstory, but the core plot is pretty dull. The maps and enemies aren't as interesting either. Great music
FE7 has great characters, is one of the longest, the best backstory (which is really what matter. The core plot isn't that special, but the backstories rule). Good music, but not as great as the best ones.
FE6 lacks a lot, but it has a more interesting map setup than most of the others.
Note: How I feel about this changes depending on which game I played last. Still, FE9 and 8 will always be considered inferior to FE10 and 7.
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS
