[DanEC]

One aspect is that the hotter the cam and rougher the idle, the worse is low-speed bucking or surging. I saw where someone referred to it as "trailer hitching". I believe that the Cobra being such a light car also accentuates it somewhat. If you intend to drive the car at all in traffic situations this can be an issue. It can be reduced somewhat by running more initial timing or maybe even vacumm advance. If low speed traffic isn't going to be a concern then a hotter cam shouldn't be too much of an issue.