ok was a good movie, I like the background it set in, rough tower block, chav mother, drug dealers etc.
My main gripes were the story of who the sniper was, , the fact it lasted a long time with noone around noticing and the continuity of the scenes as it looked too obvious scenes were filmed different times and edited together.
SPOILERS
I didn't mind it... An interesting idea... A couple of things were a bit implausible... I didn't mind the skip blocking the back door. (Though, hopefully no self-respecting skip company would actually dream of blocking a fire exit.) But, putting the booby traps in the lift and the stairs to the roof without anyone noticing seemed rather unlikely and jamming the mobile 'phone signal would have taken some serious kit. (Landlines could have been cut easily enough. Though, I don't remember anyone even trying their landline.) But, I probably turn a blind eye to more implausible stuff than that in films on a regular basis... The characters could have been a bit more interesting... My favourite was definitely Jack O'Connell's Kurtis, which, considering what a nasty piece of work he was, doesn't say much for the rest of them. But, generally, this is a perfectly entertaining little film.