You should see the last part... I thought it was good. The effects are very well done, it looks amazing - but see it in 2D, it's a dark picture, 3D can only crush the blacks and make it look like a mess I'd think (plus, it wasn't filmed natively in 3D or anything). And my main criticisms of it (like the epilogue,

) are all things straight from the book.
I agree with everything Milk said, although I can't remember the final thing exactly from the books... are you talking about the greater scale, or the 1-on-1? And didn't it end in the great/dining hall versus outside? That's what I remembered. That and I don't recall seeing a twin focused upon in the movie at all. If you can't tell I'm too lazy to dospoiler highlighting so this is the best I can do.
Also I thought the first two movies sucked donkey balls... perhaps a combo of Chris Columbus directing and JKR having too much control? They were imo too perfect copies of the book. The 3rd movie still remains my favorite... I thought that was just amazingly done, nearly 2.5 hours long if I remember but it was packed and flowed beautifully. To render the time-travel sequence that well was really impressive.
4th book was probably my favorite... long, chock-full of crap, and the shocking execution of Cedric was great combined with the graveyard faceoff with a reconstituted Voldemordt was excellent. Movie was ok too, better than 1 & 2 for sure.
By the 5th book wand battles seemed less about casting spells and more about using wands as pew-pew-pew laser guns.
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