Originally Posted by mwar99

There are two reasons I would feel the PS4's are the better mountain tire, even in the summer where the Cup 2 won't show it's issues in the cold. One - the PS4s are way less sensitive to the change in air pressure when they warm up. You don't need to air down so much at the start of your drive and if the pressures rise more than you expected the back end isn't loose because of tire pressures. The Cup 2's realistically need to be aired down quite a bit so their pressures don't get too high while driving spiritedly. Two - if it happens to rain the PS4's will provide much better grip. In my mind the PS4's (Haven't driven the 5S so I would expect those will probably be even better) are the mountain driving tire that make the most sense for 99% of people. I never was shy about driving Cup 2's in the rain, but the PS4's are so much better in that scenario.

Originally Posted by BoxKing

Cup2s vs MPS4 on a dry track are far more confidence inspiring. I only ran the MPS4s back in April bc I was late to remember to swap to the Cups before the event, though it worked out for me with the weather that weekend being 35-40*... and my first ever event, so I was hardly consistent enough, or knowledgeable as to how much better the Cups are vs MPS4 (at track). I have had no problems on backroad drives keeping up with any of the fellas on the MPS4. I like the way they absorb the unevenness of the roads out this way, along with knowing there is less chance for me to get a puncture. I forgot how much stiffer the Cups are when I put them back on the car a few weeks ago. Its like driving on cinder-blocks vs MPS4, but I like the harsher ride feel they provide... and then I like the cushy feel of the 4s as well.