>
> For future reference, I'm wondering about the "flawed design"
> description and how often this cracking/breakage happens.?

Early 3-4 hubs had three square-bottom notches, which would develop cracks
btween them. Later 3-4 hubs had the notches radiused. There are some reports
that even the new 3-4 hubs can develop cracks, but not with the same
inevitability as the old design.

GoWesty actually has a prety good write-up  on this, with pictures:
<http://www.gowesty.com/3-4syncrohub.html>

--
John Bange
'90 Vanagon - "Geldsauger"