Redwall is not one of those children's books that's good for adults, too. It's a quick, easy read, but I found it to be quite one-dimensional. I saw very little personal growth in any of the characters (especially the hero, Matthias, who was seemingly transformed overnight into a warrior, and then remained the same for the last 95% of the book). There were dozens of acts of violence and torture described, enough to take away from my enjoyment of the book. And although there was a lot of gender parity, including female warriors, I didn't appreciate the way Matthias's love interest spent all of her time in the kitchen except when she was delivering food or drink to the troops.
All that being said, the plot was engaging and fast-moving, and there was that element of the quest and heroic journey that is so compelling. In addition, Redwall contains an entire fantasy world of mice, sparrows, squirrels, badgers, etc. that was rather cool. And I imagine my 9-yr-old son would quite enjoy it. So, three stars overall.