I heard good things about Sumatra. I picked foxit because download.com had good things to say about it. Download.com has nothing to say about Sumatra, not even user reviews. I trust them. They catch a lot of bad things before I download something. And Foxit had a few more features than Sumatra. Also Sumatra is open source and Foxit isn’t. Open source programs make me nervous. Foxit’s site seemed to me to be more professional.