Should I Buy Ortlieb Pannier Security Cables?

Would anyone recommend buying the Ortlieb Pannier security cables?

I never even knew they existed! Seems pointless to lock the pannier to the bike when anyone can just open it and have a rummage anyways. 
There's a cable that locks the handlebar bag to the bike and you can then lock the handlebar bag closed as well. Granted, it's just a piece of string that needs to be cut to bypass the lock, but it would stop a casual thief.
- Yeah, I'm aware of the string on the handlebar bag. I used to have one of those bags, but I dislike how far out the front of the bike it puts the weight - even if there isn't a lot in it. Never used the string.
Well, it is probably more convenient for a thief to take the bag and then search through it at some other calm place than search through it at the place where the bike is... The gain for a thief stealing my pannier with used stuff in it would be minimal. But the damage to me would be enormous... I do occasionally attach the panniers with a Kryptoflex cable to the bike. That will not prevent anyone from still opening them or cutting the Kryptoflex. But it prevents someone from just effortlessly taking the panniers.
what do you mean, pointless? The pannier bags can retail at around $60 a bag. That's a loss of over $100. Purchasing a little rap around lock is a good idea...
- Big market in stolen panniers, is there? The stuff IN the panniers is far more valuable. Perhaps these solve a problem in very specific use cases, but for most touring cyclists, they aren't necessary.
Again, I think you are rather missing the point. It doesn't matter if there is or isn't a big market for the panniers. The thief will take the panniers and then stick them on his own cycle and cycle away and then rifle through the gear in the panniers. Think about stuff before you make comments...
ha, Ortlieb bags run around $280 a pair...not cheap, I just bought a new set to replace my 18-year-old pair.
Just another gimmick to get you to spend money
I never have. Someone really has to be desperate to pinch your panniers, especially when you've put a few km on them, your undies, etc.
I add 4 cable ties to my panniers but then my ride is never left for very long, into the shop and out again in minutes.
I got them... The idea is to make my neighbour's panniers more attractive to nick than mine. Won't stop a determined attack, and always remember to secure them or they turn into a hazard.
Make one with brake cables.
I made my own using the much thicker cable you buy at the hardware store by the foot. Only use it for quick short stops. The one they sell is very thin and can be cut easily with a simple Leatherman but it stops the opportunities from a quick grab and dash attempt - they don't want to be seen going through your stuff. Too obvious and too time-consuming. If it's "work" it's not worth their time.
I like to tie them together thru the wheel... Just to annoy would-be thieves a little more.
buy abus combiflex. only 15 euros. same price but lock included.