PC World: This review praises Copernic 3.0 for the way it "displays your results in a clear, easy-to-understand manner." The main differences between the Pro and free Home versions are well summarized here, including the ad display in the free version -- but the author isn't sure the Pro version's advantages outweigh its cost.
Download.com: CNET editors give this slightly earlier version of Copernic Desktop Search a rating of four stars out of a possible five, but more than 100 users give it a slightly lower average rating.
Snapfiles.com: Editors at this download site give the free version of Copernic Desktop Search a perfect five-star rating, but the average rating is only four stars from about two dozen users -- some of whom complain that version 2, though problematic, still provided more features than the only free version now available, Copernic Home 3.
Lifehacker.com: Copernic earns kudos in this comparison review for its excellent previews, but a poll of over 2,000 (mostly tech-savvy) readers ranks it toward the bottom in popularity.
PC Pro: This older review gives an earlier version, Copernic Desktop Search 2, top ranking among five desktop search engines, rating it five stars on a six-point scale.
Kalio: Older objective tests here find Copernic 1.6, a much earlier version, faster than Google Desktop 4 but slower than Yahoo!
MusTech.net: Joseph M. Pisano, a musician and fine-arts professor, gives Copernic a rave review based on his personal use of several free and paid desktop search engines, including Google Desktop and the search built into Windows Vista (Desktop 4). Copernic wins points for excellent previews and overall ease of use.
Web Worker Daily: This reviewer praises Copernic Desktop Search for its speed and the fact that it doesn't slow his system, finding it faster than the search built into Windows Vista.