Well clutch master/slave cylinders are only there in ones with the manual transmission..For automatic transmission it's a totally different ball game. I think most of the nissans have CVT for transmission, which means seamless speed ratio change.

As far screwing up the cat converter goes,,it can happen with any car if the things like O2 sensors are not taken care of in time (Check Engine lights ignored) and the elements of converter made to overwork and subjected to emission particles beyond the design limits.

The technology has advanced by leaps and bounds in past few years,,it's hard to compare one brand with the other based on 10 year old model, when hyundais were considered as junk, KIA's were worthless. It's not same anymore that their 2.4 lit engine produces 200hp/6000rpm while toyota's and honda's rate at 175hp for same engine displacement. And yeah of course there was a time when GM, and Chevy were the best automobiles.

And yeah even the BMW's and Audi's start giving problems around 100,000 miles.

So go with what you wish,,and how your budget is.