hi hi,
not sure better in what sense....just that i read somewhere got pple recommend a lens with a particular f-number but someone else recommend a smaller one....so i thought is it the smaller f-number is better....
if you can afford it, get the f/1.2! ;p
My point is, f/1.2 is smaller than the f/1.8 and f/1.4. If you listen to your friend, you'll be getting the f/1.2. Ask yourself, is it worth it, what is your style and do you need it? Borrow from your friend and try out for yourself. See if you like it, suites your style etc, then go out and get it.