I've been through passport control scores of times wearing a hair system and it's never an issue. Of course, I imagine that when you go through a full body scanner the person on the other side must be able to spot you are wearing a system: but they must see all sorts of things day in and day out and as you don't see that person and it's all over in seconds I really wouldn't worry about it. I have changed by passport photo to go with my system, but as people change their hair style frequently I don't think that should bother you either.Has anyone ever had problems at passport control after getting a hair system.
Passport will have your photo prior to you getting hair.