Catalytic converter Q

Is the "universal fit" in any important way different from the ones that come up "direct fit"?
All I can think of is that universal fit cats will need an o2 sensor bung welded in, while direct fit won't. Is this the deal or is it something else?
Having trouble finding a California-legal part for less than 150 bucks...
Any ideas?

Poke around this website, best prices I have seen on CATs, with or w/out bungs: http://performance-curve.com/425250-25catalyticconvertero2.aspx

Universal fit sometimes won't have the right flanges to mount up to your stock exhaust system. For instance I can pick up a universal for my '91 for 50, or a direct-fit with the right length inlet/outlet tubes and the 4-bolt flange already welded on for 100.

Direct fit means it already has the flares and brackets, universal fit needs to have those fabricated and welded on