God of War has always done them well. They are quick and easy, but still very visceral and exciting. Plus, they are well integrated into gameplay, giving you multiple options when dealing with enemies. I do wish their was more variation in the animations, but that isn't the fault of the QTEs.
Shenmue did them well too, in the same vein. I actually got to the point where I preferred the QTEs to an actual fight, simply because the QTE scenes were well directed and I enjoyed seeing them.
Bayonetta is a good example of a game that does them rather poorly. The torture attack button mashing is ok, I guess, but the mid-cutscene ones just come out of nowhere and are very easy to fail if you aren't paying enough attention. And failure usually equals death, ruining your chances for a good score on the level.