It was at times pretty brutal but not in a senseless way, more like in a this-shit-actually-happens kind of way.
Bit lengthy at times, bit predictable but in a way that it delivers to my expectations and sometimes more.
I found the characters though somewhat clichéd to be believable more than I usually due thanks to the extra length that gave them time to be more than a ragdoll.
Kept me interested, kept me entertained, would have been better without the non-ending (makes sense when you see it).
The biggest problem I had with it was how it was the main characters lack of urgency and complete naivety that got them into the mess which was also the plot and which made it hard to relate as of first but you grow to like them as they mature to the situation.
All in all a good movie and for a change something it was something refreshing in the action-thriller genre.
EDIT: Blake Lively is fucking hot as fuck.