Coming from Thailand's neighboring country, I can relate to the premise of the movie quite well; an urban metropolitan and hectic lifestyle where public transportation and rapid transit seem to be the only dot connecting everyone. As simple as this is, the traffic provides the right setting to develop the majority of the movie's fundamental themes.
Let's settle the flaws first. Yes, the movie can get draggy at times and it may seem like a rather tedious task to watch, but I don't necessarily think these parts are fillers per say. These little nuances, as irrelevant as they seem, are important in building up the character of the main leads. The tiny pieces of informations coming from different parts of the movie patch up any doubts the viewers have towards the leads; they are romantically-flawed individuals yes, but each of them have their own reasons for every action of theirs, and this actual sense of insecurity connects us with them.
Retrospectively watching this after watching Cris Horwang's stellar acting in Seven Something (2012), I finally realize what is it about her that enables the audience to love her. She portrays fragility and femininity very well. Her acting embraces her flaws; she doesn't pretend to be devoid of weaknesses, and this 'flaw' of hers makes her acting relatable to an average city dweller like you and I. Elsewhere, I've read comments about Theeradej being somewhat stoic in this movie. I would say that I find it perfectly fine. Being an engineer that has been working the night-shift for a long time, he symbolizes loneliness and being unable to somehow express himself. I mean, how often do you see a girl that is human after midnight? He fits the role perfectly, and he's perhaps the sole reason behind the popularity of the movie among the girls.
As a whole, I thoroughly enjoyed the experience of watching this flick. I find myself really loving the Thai's way of making romances; stripping them of any overly-dramatic elements and just making them as close to reality as possible. Who cares if its draggy at times? As long as viewers finish the movie with a smile across their face and feel more appreciative of their partner, I'd say this movie worked pretty damn fine.