Great watch, will watch again, and highly recommended.
This has a wonderfully exciting premise: alien refugees on Terra, how Terrans react and how the aliens react. The premise, as delivered, has some odd holes in though: it's specified that all of the crew have died, mysteriously, and no one knows how to operate the ship, but it's been in the air for some time. The idea of gravity alone should have motivated Johannesburg to evacuate, but their government interaction seems decidedly weak.
The advantage of setting the story in South Africa, for an American audience, is that it's a very capitalistic society where they speak chiefly English: it's very similar to being set in Mexico and using Mexican Cartels instead of Nigerian gangs.
So if we accept that we haven't been able to extract an incident report, that we're not able to move the ship, and none of the xenos can move the ship, then the premise includes that one xenos knows what to do. One would think that he just talks to someone and he gets all his people off planet, but since he's smart enough to do what he's been doing for 20 years, then he knows not to trust anyone. But this self-serving principle is key to understanding character motivations going forward.
The writing in this is so good, along with the effects, and performance delivery. As Vickis deals with his transformation, it prompts so many philosophical questions of what it is to be a person / human / xenos, a citizen, a government agent. It also sort of resembles a gangsta / heist movie at parts, as opposed to a anti-government escapee.
If any of the deep stuff worried you, then be at ease that this movie has plenty of explosions, gunfire and sci-fi goodness. It's also filled with some silly cliches that serve the points of the story, but there are several points in this movie that I have to shake my head at. The motivations don't make sense unless you're reminded that everyone, including the protagonists, are (forced) in a self-serving mindset and it's about what they can do for themselves, even when working together with the contrast being, of course, that only when anyone is cooperating that anyone gets anywhere.
This is such a great watch, and if you like sci-fi styled stuff, and don't mind the South African setting ("Chappie" is another one), then definitely give this a watch.