(I would also like to let readers know that I've seen half of this anime. I may not have watched it all, but I did give it a chance.)
Plot:
Even those who loved it will agree that there's no plot. I can extend that and tell you that, if you're looking for something with depth, don't look here. I didn't find any; and I looked pretty hard. The focus is instead on repeated jokes and silly/dumb/immature characters (Osaka anyone?) getting into "amusing" situations; none of which I found that amusing...
Characters:
I found all of the characters a bit grating, aside from the taller girls (who didn't really talk). Their childish demeanours made it feel like I was watching something aimed at young children. Despite there being a couple of underlying truths about (some) people in the ways the characters acted, I can't say I identified with any of them.
Humour:
Comedy is what this is praised highly for, right? Well, I couldn't understand why... Not only did it not work on multiple levels; the repeated jokes (e.g. one character getting bitten by a cat; flapping pigtails making the girls fly) just felt unwitty and chidlish. In short, they did nothing for me. At the end of each episode I couldn't help but feel it had all been a waste of time and money.
So what're its redeeming qualities? Uhm. Well, the animation itself is pretty nice. Each character has been designed well physically to match the personality of their character. The quality of the DVDs is good... There's a choice of dubs and subs, although whether that's a good thing depends on who you are. Apart from that... I can't really pinpoint any.
