Saw it last night at the BFI IMAX
And I thought it was a fantastic film - really enjoyed it. Didn't feel like it was too long and the editing seemed pretty tight. (OK, couple of places where it could have been tweaked, but nothing detracted from my enjoyment of the film.) Didn't really notice the time passing and found it thoroughly engrossing. You do have to stay awake though, or you can get lost in the plot - five of us went last night and one person lost focus a couple of times and found it hard to follow and much less enjoyable after that.
I'd thoroughly recommend seeing it
and yes, who'd have thought a van could take that long to fall...