Okay. This paragraph only. It is becoming annoyingly predictable who and what Hollywood will or won't allow to be villains. You know full well that the guy in full Muslim garb is not going to be the bad guy, don't you? I don't mind that so much, because it plays on people's fears and prejudices - average people on a plane are likely to unfairly profile that guy. The problem is that once I tell you that person is not the bad guy, I'll bet you can kinda guess - using every caricature of modern movies that's out there - what sort of villain we are in fact dealing with, and what their motives might be. After leading us on an enjoyable wild goose chase that finally gets to the "who," you just kinda wish they'd shut their mouths about why.
ZOMG! Fake Geek Girl!!!
That aside, if you can put it aside, the script by former WWE writer Chris Roach and reality show editor John W. Richardson is nicely structured (if not always believable) - the murder every 20 minutes gimmick establishes a constant ticking clock, and the suspense over how it can be done without the killer showing his or her face is clever, all while building to the bigger question of what the end goal is. It's marred by the occasional stupid misstep, like the aforementioned racism and the overly theatrical "hero speech/12-step confession" Neeson gives to all the passengers late in the game so as to rally them to his side (very un-federal agent-like). Those are things you'd forgive if the overall film were campier, but to coin an image I'm sure one of the writers would understand, you don't throw Hulk Hogan into an MMA match.
I can't entirely recommend Non-Stop, but I'm also not completely immune to its charms. How much you can weigh that balance will determine whether or not you feel the same.