First, a basic overview:

Story:
Ai Kora's premise is just like Love Hina's: a boy is conveniently allowed to live at a girl's dorm.
Art:
Ai Kora's art is just like Love Hina's: even the characters bare some resemblance.
Character:
Ai Kora's characters also share some resemblance to Love HIna's characters. There's a ninja, an older alcoholic, a 'tsundere', and an innocent. The characters in Ai Kora do change throughout the story (despite what some reviewers might tell you), though, these changes are either changes in self esteem, their views on Hachibei, or, some combination of the two. Hachibei himself does change throughout the manga (though it is a slow paced change).
Enjoyment:
Ai Kora does well both in the humor and 'romance' angles. There is not much ecchi, for those of you who enjoy Love Hina or Negima, but when ecchi is present, it's a treat. The manga is easy to pickup and read. The plot, despite being paper thin, is enjoyable. Hachibei, unlike Love Hina's protagonist, is likable and assertive in his goal to ensnare the attentions of the girls living in his dorm.

Despite all the similarities to Love Hina, and despite the usual 'auto-fail' harem manga usually become, Ai Kora seems to succeed where most others have failed. Hachibei is a different kind of harem protagonist, one that is perverted, but righteous in his perversion (and somehow, paradoxically concerned with maintaining a woman's purity). The girls themselves, while seemingly flat - do change their ways and grow to accept themselves and Hachibei. Where Love Hina and other harem manga stagnate (because the author is unsure how to pursue the story angle of a character maintaining polyamorous relationships, or how to properly divide plot space between the numerous characters), Ai Kora does manage to keep the reader interested - by maintaining a sense that Hachibei is winning over the girls' affections, slowly (whether he succeeds... well, I won't tell you).

Overall, while Ai Kora lacks the creative idea that startred Midori no Hibi (this author's other work), Ai Kora is an exceptional romance/humor manga that is manages to avoid failure and leave the reader usually satisfied at the end of each chapter. It is not worth passing up, if you can find the time.