I have just purchased a this product for my home use and find it very good both for home use and office use. This resolution is what the scanner sees negatively and should be used as a baseline when comparing similar priced units.
Going above this resolution (600 dots per inch in this case) will result in interpolation, which in many cases can degrade the quality of the image (since the hardware or software ’guesses’ at the extra pixels by analyzing the pixels around a specific area).