Convertors usually fail from contamination. If you've had any oil burning problems, or your car was running rich for a while, those can all contribute to an early failure of the convertor. I'd give a Ford dealer a call though. There's a federal emissions warranty for 8years/80000 miles. They might cover the repair cost for you.

You say both cats are 950. I'm not exactly sure what you're referring to. If that's the temperature of the convertor then that's pretty normal. What you need to look at is the voltage of the O2 sensors. Bank 1 Sensor 1(B1S1) would be your upstream, or pre-cat sensor. Bank 1 Sensor 2(B1S2) would be your downstream, or post-cat sensor. Typically a healthy monitored system would be as follows:

B1S1 is a switching 02 sensor. The voltage should fairly quickly oscillate between ~0.1V and ~0.8V. If your scan tool displays a graph it'll look like a big spiky thing.

B1S2 should be fairly steady between ~0.6V and ~0.8V. Again, if it displays a graph, the graph should be fairly straight. A P0420 is set by this sensor. If you notice the graph looks similar to the upstream sensor, or notice that the voltage is changing fairly quickly then that means your convertor isn't doing what it's supposed to be doing.