Why does so-matome have an n1 vocabulary book and a separate tango book with 1500 more words than the other?

I was looking into n1 vocabulary book and so matome has a n1 vocabulary book for passing n1. It states it will teach you 1300 words. But then I found they also have a word book with 3k essential words for the n1. So which one am I supposed to get?

Has anyone bought both of them or one of them and tell me their experience? Was it enough to get the normal one or do I need the tango book?

by QuickSwordTechIrene