(which is why they changed the design, the connection was not a secure one).
What isn't secure about them? They lock. I've never had one come lose in the field.
It is what I heard but I do not recall the source of this claim. I have used my KA100s with no connection issues but they have been in the field only a handful of times.
I don't think it was a secure thing at all.
The old KA 100 was an expensive and unique adaptor - when they made the LC3-KA cable, it made sense to use the new bottom end and put a Lemo socket on the end of a short cable. Especially as the KA 100 would now only be used by old units and for users of the floor stand that still had to use a Lemo as it was threaded down the tube.