Mostly all reviews praise this show, with a lot of comparisons with Hometown Cha Cha Cha (and rightfully so). There was a lot to like about it, but there were numerous things that really bothered me, hence my lower score.

What I liked:
-The acting by all was very good, but I did find Shin Hye Sun's constant pursed lip/pout talking very irritating after a while. I have loved her in other things she's done and never noticed her doing it before. I loved the friends, the families, the townspeople, and Samdal-Ri's little niece was just precious.
-Jeju. The cinematography was just stunning, and if this doesn't increase tourism, I don't know what will.
-I really like the idea of friends that have known each other for years, supportive of one another when apart, and then coming back together like no times has passed.
-2ML. I may have seen this actor in another role at some point in time, but I really liked him here. He had that almost palpable sadness surrounding him. Though it's not really realistic for someone to have one-sided love for that many years, the romantic in me just loved it. I also like how he was at odds with himself as to whether he should tell her or not. On top of that, he was just such a good friend to both the ML and FL.
-The sisters' storylines were well-developed and didn't feel wasted.
-Happy, though lackluster, ending.
-The friendship between the ML and FL. Which brings me to...

What I didn't like:
-For me, there was no chemistry between the leads. I loved them as friends but didn't buy them as a couple at all. Add to that that he thought she broke up with him, she thought he broke up with her, and all I could think was "how hard is it to just talk to each other?"
-So much drinking
-Drunk confessions
-The way the FL was written was problematic for me. She was portrayed as this strong, independent woman, but yet she slinks quietly away when the woman made up lies about her? She doesn't stand up for herself. She attended a long pity party for herself. I realize that the lie was pretty much the whole premise for the show, but it could have been written much better.
-Working with your ex? Nah.
-There needed to be a more satisfactory ending for the evil girl, she just kind of went away. I'm not a big revenge person but come on!
-After the 8-year (I think that was the amount of time it was supposed to be) time skip, we get another two-year time skip at the end. And that one made no sense. Suddenly he's going away to "realize his dream". Throughout the first part of the show, I really got the feeling that he NEVER wanted to leave Jeju.
-The ML's father's story line. It was immature and went on too long. If he was that troubled by Samdal-Ri's family, I'd think he would have moved away or something.

If you are still reading, I'd say give it a try, you might love it. I'm definitely in the minority.