If you find it is that cat, and need to replace it, don't leave it in all the time. Have an exhaust shop build a test pipe for you, tell them it's to put in while drag racing or something. The test pipe bolts into the spot where the cat goes normally. It's just a piece of straight pipe. At the performance shop I worked at for a long time we found that aftermarket cats barely last the two years in between tests if you leave them in. I use one in my '91 Jetta. About a week before testing I throw it in, drive it normally, go through my test and then put the test pipe back in. Then, I store the cat until the next test.