I've been enormously impressed with iText in that for as long as we've been using it, we've almost never had it blow up on a PDF that Adobe Reader could render. We get data from all over the world, and process it for the legal industry. We get a lot of corrupt files in varying states, and have to "deal with it" as best we can. To date we've processed more than a million PDF's from every corner of the civilized world.
Robert Simpson from kCura