Well,
First of all, as many reviewers have pointed out - this is a rip off of the Martin Cahill story - first represented by the BBC and by the John Boorman film "The General" - which is a great film and far, far superior to this one.
Speaking as a native British person, the supporting cast to Kevin Spacey was really good in terms of British and Irish acting talent, especially Peter Mullan - but it was totally wasted. The characters were c**p! And as for Kevin Spacey - didn't come across as a loveable rogue but as nothing really substantial or significant.
Not a lot to redeem this film. The best bits are the gags and tricks nicked from the other films it rips off. Compare notes on this film and "The General" - I'd be interested to see what others think.