Thanks for the info.
The rucksack cover looks like a good idea but my suitcase is the middle sized one (45cm wide and 75cm high) and I'm not sure if it would fit inside one.
I'll have a look at a few shops over here though and see what sizes they come in.
Quoting Swept Away
The tiny padlocks can easily be opened. I learned the hard way.
If you fly with tiny cheap locks on your bags just hope and pray that the baggage inspectors only "cut" the locks off and not just rip your zipper apart for spite! I used locks early on believing that if needed the TSA inspectors would simply cut a cheap lock off - nope! They ripped the zipper apart or cut the pull tab off and left it dangling!
Since I switched to the electric cable ties I have never had my zippers or tabs destroyed - plus they never even inspected the bags by hand either! And that has been a heck of a lot of flights since NineEleven!
(I do use locks on my bags all the time when I am not flying though.)