I would say… both. Not everything is good about the show, but a few episodes really pay off. I would suggest to watch the complete first season and the overture of season 2; if you don’t like that don’t bother to go any further (the middle of season 2 is boring, it gets better a handful of episodes before the ending season). Season 3 is a huge disappointment which barely uses the finale of season 2 and which goes in another direction of stand-alone tiresome episodes. It’s however important to be familiar with the previous series, The Clone Wars, otherwise you wouldn’t appreciate Ahsoka and Rex story arcs.