Definitely worthwhile. I chose my challenges to get me to get a better variety in my reading. It made me finally read some more John Steinbeck. Cannery Row (40s) is probably the best book I've read in a few years. Richard Matheson's I am Legend (50s) is brilliant and I finally read some John Updike (60s).
Only three letters left and I'm done my challenges. I'm currently reading Y, another D, another P and another R. I'm not really looking forward to my W selection, but it's one of those I should read something by this author choices.
-- A B C D E F G H I J K L M N O P Q R S T U V W X Y Z --
-- 19-C 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 --