The storyline, like others are saying, is very predictable and kind of corny. It is the typical old friends realize they like each other after seeing them with other people. I'm not even going to watch the second season because I (accidentally read a spoiler but also) can completely guess what will happen.

I don't think that the chemistry of the actors was that good; I enjoyed the main two as friends, but didn't feel the romantic tension they were so clearly trying to insert. Do Hyeon was cute with Song Yi but nothing heart fluttering like most people want.

Mostly the acting was good, but I have to say, Choi Hun, or Kang Tae Oh, was pretty bad. I cringed quite a lot watching him overact to the EXTREME. It was way too much. I felt this a little with the main male lead, Ji Soo, as well (but not as extreme).
Overall, its fine, but I do regret watching it because I could have been doing somthing much more productive with my time.