Yeah, don't think of actually buying any knives over here if you are a US citizen, prices are way too high compared to US prices. I wouldn't worry too much about police searches, the actions in the past were large organized events, which you could identify from afar. I think there was plenty of time to turn around and walk away. Besides, I believe the police did have to ask your permission to search you, and most (if not all) of the actions have been deemed illegal in court. I haven't come across any random searches personally. Have a good holiday!