So you have all the hot features like split second fail over and all that mother jazz, but your network stability with version 4.1.5 remains, well, far from desirable.
Because you are an important customer who spends a lot and is high profile and you have all these nasty blackholes & links that are being shut down, you get a change to come over to the heart of the provider's R&D to run your own tests on their testbeds, since their tests are "single featured" only and you, by design, need most of the features at the same time.
It takes a day or two before the agreed hardware configuration is finally ready, First minute you go start to work on your test plan... the 4.1.5 software fails.
Panic at the provider.
Developers are being called in.
Source of the issue determined.
New release build.
Calming phone calls are made.
New release silently tested by developers.
Next day first step of the test plan works.
Guess what: step two fails.
Fly home and have all sorts of important people fly over, do meetings, dinner invites and what have you.
After a month, the all clear signal comes and again you pack you bags, fly over, do your tests against 220.127.116.11: all succeed.
Confident and relaxed you go out, have a couple of drinks and fall in a deep sleep back in the hotel. Next morning you grab your stuff, head for the airport and receive a phone call from your colleagues on the other side of the pond. They where awake while you where enjoying your well deserved sleep. Bad news:
The version [18.104.22.168] you have put so much trouble in testing, has just been retired while you where asleep.
As I wondered about before, I do not know who uses this... product, but I do know who will soon not anymore :P