There should be an earlier discussion of dictionaries sometime in the last year. Are you looking to buy this in the US or Spain?

For my "pocket" Spanish/English Dictionary I chose the Cambridge Klett because it was easier on the eyes. I waited until I got to Madrid and went into a big bookstore where I could look at a huge selection for side-by-side comparisons. "Pocket" is in the eyes of the beholder since any good one is the size of a good-sized paperback. The Cambridge Klett also has a stiff cover so it doesn't get tattered being carried around. Several of the other smaller ones also have this feature.