Reviews saying this show is Teekyu played at 50% speed are pretty much correct: the premise, the formula and even the characters are rather similar. It follows the four girls from a rival tennis club of Usakame High School, that had a few appearances in Teekyu. Ayako Suzuki, the central character, plays the same role as Yuri, being the voice of reason in the group and actually being interested in the sport itself, while other girls are mostly goofing around (or participating in the club activities just to be near Ayako - there's a subtle yuri subtext to the main story-arc). The humour is of similarbrand as in Teekyu, quite random and abstract, but its definitely slower (that's possible thanks to the 4 min episodes) and toned down (also when it goes to adult themes, which are almost absent here) - whether that's a negative is very much a matter of taste. I actually found this show very relaxing and much easier to follow, not as funny as the main series, but very much enjoyable in its own right.

I also have to say that I liked the music (especially the opening song) and the art-style quite a lot. The animation is simplistic, but with its minimalistic style and pastel colours it feels like a sketchbook brought to life - a very nice artistic effect in my opinion. The voice acting sometimes falls flat, due to the cast not being professional seiyuu's (the show is pretty much a giant advert for Earth Star's idol unit and the girls from it voice the characters), but for the most part, it works fine.

In summary, I was actually surprised by how enjoyable this show was, considering the below-mediocre reviews it gathers - it was different from Teekyu, but in a cute and mostly positive way. It's not even close as wacky and doesn't have many "laugh out loud" moments, but if you can get past that, you'll find a very nice and feel-good little series, definitely worth that hour of watching the whole 12-episode season takes to finish.