Pre-rendered cutscenes will always, from this day on to eternity, be better quality than "live" cutscenes run on the game engine. Simple reasons apply. So, it's a question of whether we want rendered video or not. I'm personally a firm believer of having rendered intro and outro videos, and the more there's rendered video in between the better. It's understandable, however, if someone doesn't like the differences between the engine and rendered video.
However, the videos the guys at Blizzard, Square and so on have done, have always been pretty awesome. I'd much rather keep those guys employed, rather than have the game engine run the cutscenes.