we are evaluating IEVision in order to detect faces. The available classifiers give us mixed results. Is there any developing or progress regarding these classifiers or are there any other classifiers available which produce better results?
The included classifiers are a collection of available OpenCV pre-trained ones. You may be able to find better ones or you might want to train one yourself (see the TrainCascadeClassifier demo).
Also the upcoming release supports Neural Networks. Though there is no built in model for faces, again, you can train your own model.