If you love young ladies who activate their witchiness by growing fluffy ears and a bushy tail, before flying around the sky and trying to shoot alien spacecraft with world war 2-era guns and/or the occasional samurai sword - then this is for you.
An added bonus, if you like that sort of thing, is regular and increasingly creative shots of the girls flashing their 'pantsu'. Of course, the plot requires for them to be wearing no trousers*, so they can fit their legs into their witchy broomstick apparatus.
The plot is your standard 'young girl with abundance of raw talent joins more experienced crew and overcomes adversity and jealousy by saving the day on several occasions whilst learning and growing throughout the series' type-set-up. But as ever, it's in the delivery, the dialogue, the sheer joy and fun and (quite literally) cheekiness of the thing that sets this apart.
All the characters are archetypes of their nationalities - I wouldn't say parodies, you just have to enter into the joyous silliness of the premise as a whole.
Plus, hot pants. :)
* apart from the French one, who seems to always be wearing tights. For those of us who like to see a lady in tights, I guess.