Yes it is worth it. It's not a full volume but a selection of a bunch of best-of from the manga series. It's the first look at the long-running series, which has, for a long time, been Japan exclusive, in English. It's a lot better if you're fluent in French and Spanish since there are full volumes in those two languages (but not all the series). If you're familiar with any stories from Paper Mario, Super Mario Sunshine, Super Paper Mario, Super Mario Galaxy, Mario & Luigi: Partners in Time, and New Super Mario Bros. Wii, it's definitely worth a look.