I have had numerous problems with mine.
On a loaner bike the following happend on one trip:
After 200km's and arrival to the camp cabin I discovered a lock was missing from the left hand bag. It had vibrated loose and off the bag.
Since I didn't buy the inner bags I thought I just could release the bags from the bike and bring them in to the cabin. Well, since the bolt have vibrated loose I could only remove the bags using a lot of force. This caused one of the bags locking system to break. With the supplied BMW tools I was unable to take apart the bag on location so I had to tie the bag back on the bike to manage to get home.
At home I took the bag apart and managed to fix it myself.
Next trip, this time on my own bike, worked out pretty ok during travelling the 600km's up into Norway. While I was there I was riding arround without the bags mounted for a couple of days. Guess what, both bolts where off the bike when it was time to go home.
Time for some straps again.
After I came home I visitted my dealer. HE ordered new bolts, but they came without the locking nut. After 5 weeks waiting BMW Sweden came to the conclusion that the lock nut was unecessary and that loctite should be used instead.
I haven't been using the bags since, I have the locking bolts laying arround and some locktite.
Next time it will be Jesse bags or whatever, no BMW bags.