User blog comment:Miskos3/Episode 275: Fairy Tail Zerø: An Eternal Adventure, Review/@comment-3441749-20160313052805/@comment-3441749-20160313094001

Not counting the filler episodes, which are obviously just either one shots for laughs or adaptations of omakes, the only filler arc I've seen is the Key to the Starry Sky arc;. And while it wasn't anything great, it wast still head and shoulders ahead of any filler Bleach or Naruto has. I also liked how it gave Kinana a little more to do. And while I haven't seen the Eclipse arc (nor do I wish to) so I can't formulate an opinion on it, there was at least an idea there. There has only ever been a grand total of two filler arcs so far, anyway, so its probably too early to tell.