The app flawlessly plays any media file from an external hard drive connected to my router. Everything is neatly indexed, and the metadata is displayed in Dutch.
The only drawback is that it doesn't send a lossless bitstream to the amplifier. Audio is sent in real time in a PCM container. This isn't an issue with Infuse, but rather an Apple TV limitation. Otherwise, I highly recommend this app to anyone with a large movie/series collection.