This particular OVA starts out relatively slowly but quickly picks up. It is very much in the style of shows that favor one-off stories, rather than an important overarching plot, to enhance character development. However, in the last three episodes important details begin to emerge about the universe that raise questions that set up for further entries in the series.
The early episodes serve their purpose of character introduction and development dutifully, and are really quite funny on top of that. Amongst the early episodes, episodes 2 and 3 are particularly strong, 3 probably being the funniest of the entire series.
Episodes 5 and 6 are the most watchable and form a two-part series about a rebel group attempting to gain control over the government which really piques the interest of the viewer. The stories told throughout the OVA are mature and understated with great concern for the political intricacies of the universe, with these elements coming to a head in this pair of episodes.
Animation wise the show is very good looking for it's age with smooth animation and fantastic mecha designs. Various mecha are introduced at a steady pace and each is diverse but still very cool looking. The weakest point of the series is the voice acting. The Japanese voice acting is good, but the English dub is remarkably bad with a few glaring cases of miscasting.
Overall Patlabor is a great introduction into the universe which showcases the format, strengths, and overarching themes of the franchise. It stands strong as both an entry into the Patlabor series and a series in its own right.