> Perhaps that was not a good term, but they do depend on being properly placed so that
> they maintain pressure on the insert.

Well yeah, most repairs DO depend on being done correctly to work.

> But aside from that, there is still the
> possibility for the insert to rust

It can rust all it wants, so long as it doesn't move and continues to
support the end of the tube. The one I have in my hand that popped out
of my white van has only the slightest patina of rust on the OUTSIDE.
The inside is bright and clean. I don't see rust as being an issue.

> and the hose to get old and soft and stretch,
> allowing the insert to move.

And that, of course, would be a hose failure before it ever even came
close to a "steel insert falling out" failure, given that the insert
is 2 inches long and any hose stretched 2 additional inches within a
1-inch span is going to tear.

> Those are just my thoughts, but as I said, I have the kit in one of my Westys and I
> try to change the coolant regularly and inspect the pipe ends at that time.

Fair enough, I have essentially the same strategy. 3 years in,
everything has held.

--
John Bange
'90 Vanagon - "Lastwagen"
'90 Vanagon GL - "Wiesel"