It is difficult to put it in the right words. Vincenzo is one of a kind.
Vincenzo is the best series I've seen this year. Period. The cast, the story and the OST, everything was just perfecto. It was the best mix out of tension, intrigues, comedy and heart-warming scenes with amazing side characters and overwhelming twists and turns. Vincenzo is indeed a feelgood drama.
I've seen that some people are upset because of the glorification of the mafia, his action and the impossibility of defeating Vincenzo, but keep in mind it is just a fictional series. I personally do not quiet much enjoy action or thriller series and movies, only if they are paired with warmth or justice (can be viewed from different perspectives here...) they are an option for me. Due to the fact that there were that many unexpected turns and Vincenzo really knew how to deal with gangsters, every cliffhanger kept me going straight into the next episode.

To the main leads (all the supporting actors were great, too, and I'm looking forward to their next projects).
I knew both of the before. I've seen Jeon Yeo‑been in BeMelodramatic. Furthermore, I really enjoyed her acting, and she kinda carried the show for me. When I started watching Vincenzo, I was very surprised. She seemed like a completely different person, and I'm still very impressed by her talent.
I know Song Joong‑ki from Descendants of the Sun (DoS) and I'm so glad I do not speak Italian because I'm pretty sure he delivered those Italian lines just like the English lines in DoS. In DoS you really noticed that he didn't know what he was doing, and that he was allowed to do it in such a way surprises me. In general, I only liked him semi in the series, but that could also have been due to the relationship structure. So here it did not bother me, because of my lack of knowledge, which means I can not judge it at all. I liked him a lot in here. He embodied Vincenzo perfectly with his innocent looks and confidence.
Ok Taec‑yeon was the perfect representative of the multiple personalities and played his two roles very well. The magic happens in the eyes like I could almost grab the madness.
My personal highlight was episode 8, but obviously all of them are bangers.
It's about power struggles, friendship, the past and reinvention among most of the characters. In the end of Vincenzo, the relationship of the main leads is not defined, but I can easily say that I have not seen such a healthy relationship in a Drama for a long time. There is no crossing of borders, no invasion of privacy and if somebody told a lie, it was accepted until the person was ready to talk about whatever happened. Nobody needed to change or complement the other, they liked each other as complete individuals. They just liked being around each other and had the same goal.
The music never failed to hype me up. I really loved everything about it, but I'm pretty sure there will not be another season.

BTW since they are calling themselves the Cassanovo Family, aren't they also a part of the mafia XD