SPOILER ALERT - If you want to watch the drama with no spoilers, don't read my review. This is more about my afterthoughts now that I've seen the drama.
It gave a promising start and stayed strong until the middle. The dealbreaker for me was that he ended up with Yi-Seo.
To me, it diminishes his growth as a person. He went through so much and tried so hard, and the whole drama he was pushing her away, as he should have. She was interfering with his goal to take revenge and she couldn't accept him saying no. Yi-Seo should've stopped pursuing him and moved on. Yi-Seo's personality clashes with his all the time, so much that I was actually shocked he ended up liking her back towards the end; it made no sense to me at all.
The perfect ending would've been him staying friends with Yi-Seo and Soo-Ah, nothing more. The three would've then grown together as individuals, and they move on with their lives.
I was happy for Soo-Ah to meet the new chef (great cameo, by the way), but Ro-Yi ending up with Yi-Seo almost ruined the whole drama for me. Still, the drama is worth the watch if you can move past the weird romance at the end.