Positive:
Story-wise: pretty good, interesting concept and the author really manages to live up to the expectations of the title.
Aliens: well done, with a very otherworldly feeling (for some species).

Negative:
Human characters: rather "nah" (mostly rich men who have lived for generations and are driven by money, power and sex. Female characters are primarily described in terms of hotness with few exceptions)
Sci-fi that relies heavily on gimmickry and detailed matter-of-factly explanations (not a big fan of this style of sci-fi)
I really disliked the ridiculously reckless and unmotivated story-line of a certain character (seriously, I think the author threw this in there solely to be able to spew out more alien settings to describe).