Well if not actually the fastest, it sure may rank amongst the three top ones of this class! http://www.stdutility.com/index.html - it's also a DjVu file viewer.
For you guys who haven't heard of PDF-Xchange yet, it's another alternative to other PDF bloatware viewers out there that's worth a look, download and try (free version available and also a portable one). Here:
http://www.docu-track.com/downloads/users/
All the best from R i , Brazil.
The FASTEST-Loading PDF viewer on Earth!
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