Essentially what you need to know is:
2) The film was very well cast... obviously Liam Neeson's been doing this for a while and he's really beginning to develop a nack for his own brand of fun/funny but good action... Julianne Moore was just a very welcome surprise and once I saw her doing her thing before the flight I knew there was going to be at least a small amount of quality to this film... add in Scoot McNairy, Michelle Dockery, Corey Stall, and the Oscar winning Lupita Nyong'o and you've got yourself a pretty well rounded group of performers.
3) The cheese was not too cheesy... this film lived on action and awkward cheesy wit... but sometimes that can work against a movie... this is a good example of the cheese factor giving the movie a boost and welcome applause rather than boos.
4) The mystery really stays a mystery until you absolutely need to know... and then, when the reveal does take place, I promise everything that has happened that seemed unlikely for one reason or another really does make sense... it may seem outrageous at times, and the reveal is not of the earth shattering variety, but it absolutely works for what kind of movie this wants to be... and is.
I'm not afraid to say it, I really like Non-Stop!