I actually enjoyed Advent Children's English cast, i do believe they got some of the voices spot on in regards to sounding what i thought the characters would sound like. I do agree, there are some points in the movie where i cringe at the terrible delivery of the lines, but we must remember that it was intended originally for a Japanese audience and we only really get a 'dubbed' version of sorts.

Maybe i'm just more lenient when it comes to the movie because of my bias