Watch it, seriously. 1st of all it is a hilarious arc. Let me say it this way:
Usopp, Nami, Chopper alone on a ghost "island" (it's not really an island, but meh). It just has so many hilarious scenes.
Beside of that there are some very important moments as well. Zoro gets his new katana, which is very unique, and if you like Zoro it will be a great help in understanding future scenes.
Also you get to see Luffy powered up by uhm more than a 100, that is pretty epic as well. He could potentially defeat any1 like that.
There are also 2 other characters, which are important / used by Oda later in the story. One hasn't been used yet tho, but she surely will.
Also you get to see 2 of the shichibukai. It is important to understand Bartolomeo Kuma's actions in this arc, in order to understand some of his future actions as well. And Moria laughs like a boss.