I live 281 North past 1604, and work downtown I agree that the roads closer to down town are slick. I don’t think its dust, but some roads seem oily downtown. Every Sports Car/SUV I have owned had traction problems closer to downtown; 1992 Corvette (6spd), 2008 Trail Blazer SS (Auto), and 2007 Solstice GXP (Auto). I must say the Solstice GXP was the worst when it came to traction. The 370z in these bad road situations still out performs all the vehicles I mentioned. But I have not had any issue with the highways or roads close to where I live up North 281. Sorry I don’t usually drive on 151 so I can not comment on that highway.
But that being said I have taken the bend right before the I-35 exit coming from 281N at 90mph. I was running late but even at that speed on a hard turn the car felt very planted, no traction control lights going off at all, I LOVE THIS CAR!