--snip--
I can find nobody who understands the new CA BAR rules.  Evidently there is
no information about why the old OEM model CAT is no longer acceptable, or
why it's performance is not as good as these new ones that are required.
--snip--

Local smog guy says: There were no specific regulations or specs for the
cats, so aftermarket manufacturers were skimping so badly on the necessary
ingredients that the cats would only last a short while, basically requiring
the replacement of same every or every other smog check; Also, people were
using new cats as a short-term band-aid to hide fundamental running issues
that would cause the vehicle to fail. The conclusion here was that this was
both a rip-off of the customer and an end run on the intent of the smog
program. Apparently they now require replacement cats to be much closer to
OEM specs, hence the cost. Look for this to become a trend nationally
throughout the jurisdictions that require smog checks.

Cya,
Robert