Sometimes, an intelligent sequence of parts replacements becomes the strategy to solve the problem.
O2 sensors wear out and are not terribly expensive or hard to change. If you suspect them and are short on other ideas, then yes, I would get new ones.
The cats are a little harder to change, and might be second on the list. But a question... Since the rear sensors, assuming your car has them, don't measure cat performance, the only thing that can truly determine whether they are good or not is a sniffer right? Aren't those at every street corner in CA?
Sorry, that last comment was inappropriate.
Anyway, the diagnostics might be generic, meaning that under these conditions the cats could be bad. But that is not based on measuring cat performance in the Gen 2 Viper, just a set of generic conditions that some scientist or engineer designed into the system.
So I would as said do the sensors first if you suspect them, and then stop at the Quikie Mart for a soda and sniff test some day.
EDIT...
I think what I should clarify, and someone might chime in if I'm still incorrect, is that the rear O2 sensors
do monitor cat performance, but they don't tune or adjust A/F with that data. Therefore cat performance is passive information, and may or may not mean the cats are good or bad, since it really does not try to fix the problem if found. Like by leaning the engine out some before pulling a *** dude, we think your cats are bad.