I bought the same locks in the bright lime color at REI a while back. I've used them a number of times on checked luggage for domestic trips. No problems.

I did have problems in the past with combination locks, they tend to get ripped off the zipper loops, rendering the case unlockable. I think it's because they are bulky and get caught in the luggage handling apparatus.

I always carry spare keys (locked one inside a case in Munich one time and had to take the suitcase to a locksmith to get the lock cut off), and spare locks. I usually take my little packet of cable ties and use those for international trips.