Maximus:
Have a good time but be careful.
The remarks about Britain are true - its very difficult to carry anything there.
But the point I keep making remains true nevertheless: if you dress like a gentleman, and act like one then your 4 inch knife becomes a gentleman knife. If, on the other hand, you dress and behave like a jerk - then your SAK suddenly becomes a menacing weapon.
Further - refrain from pocket carry - go for IWB (behind the belt) so it is allot harder to notice the clip and realize you are Carrying some sort of knife.
On top of that - as my gunsmith likes saying: as soon as you land, go to any supermarket, get yourself a good cooking knife - a 5-6 inch blade - Victorinox is a good choice.
Wrap it with brown paper or the paper given in the store, and put it in your bag.
If questioned - you just bought it and are on your way to the hotel..
If in need - you have a 6-inch knife - more then enough for fighting
If it gets confiscated - well - its just a plain kitchen knife and not your decorated one in a million Sebenza...
BTW - if you always have your super tool or some other multi tool with you then you have some blades for general use. They are just a little harder to get to.
And for god sake - don't take out any knife you may be carrying for any reason apart from defending your life. If you will use it to cut the stake in a restaurant - well - you may get grilled yourself.