....But the extra time taken to remove and inspect the Cat converter (since it's attached to the manifold) is more productive.... Some people just want to get the bolt out and the heater in and don't care to inspect the converter for wear.
OK, so what am I looking for if I'm staring blankly at my Cat?
You want to make sure there are no chunks missing from the gridwork. You should also be able to see through the gridwork. A good way to check that since the VX CAT isn't straight through, is to shine a flashlight in the bottom opening and see the light when you look through the top.