*sigh* The only drawback for this great game is the massive amount of post-hype given to it. It doesn't deserve it anymore, there are games that surpass it in graphical and story quality now, so it deserves to be an antique gaming gem but most certainly not the best game ever made. That just shows fanboy-ism, which I personally think dissuades other people.
Okay, now that my mini-rant is over, here's what I have to say.
For summon, yes, Knights of the Rounds is indeed extremely strong, but it can compete with FFVIII's Eden for LONGEST SUMMON ANIMATION EVAR. >_< If you use W-Summon can expect to get a can of soda and get back and still be watching the animation.
Favourite moment. Well, I haven't played it in a really really long time, but I guess you could say that time when Tifa got herself pwnt by Sephiroth in the flashback sequences, and was sent rolling down the stairs and she still lived.