I agree with Ids, especially on A7X stuff. The rhythm stuff seems right, and the leads, while note-correct, often seem like really awkward fingerings.
When Trivium did a Hal Leonard book, I tweeted at Matt and Corey asking if they contributed, and Corey confirmed that he, at least, worked very closely with the transcriber. That was their individual case, of course, but that let me know that HL at least TRIES to work with the artist.