My search for reference-quality blu-rays had a close call last month, as I narrowly avoided buying one of the Transformer films just to have them. Instead, I went with a movie I can actually stand, Avatar.
This movie was like a gosh darn roller coaster in 3-D, and the computer animation was the most convincing I'd ever seen. However, even though the blu-ray is probably the best ever made, it can't make the Na'Vi look like they're anything other than cartoons. So half the movie looks like a cartoon. The 3-dimensional effect is the only thing that made Cameron's movie look like the greatest achievement in visual effects ever. And the other half looks like it was shot on home video. The whole movie might just as well have been made in a computer.
If I had wanted to buy a cartoon on blu-ray, I would have bought Toy Story.