To those who think ESC is not important, please think again. ESC is more than just minimizing roll over accidents in SUVs. It helps the driver of any vehicles regain control if they unexpectedly hit a slippery patch of ice or water. It is an "intelligent" system that will apply brakes to individual wheels and also reduce engine throttling to keep the vehicle in its intended path.
Here is a link to the press release from IIHS on the subject of ESC:
http://www.iihs.org/news/rss/pr061306.html
An excerpt from the press release:
The new research confirms that ESC reduces the risk of all single-vehicle crashes by more than 40 percent — fatal ones by 56 percent. The researchers estimate that if all vehicles were equipped with ESC, as many as 10,000 fatal crashes could be avoided each year.
"The findings indicate that ESC should be standard on all vehicles," says Susan Ferguson, Institute senior vice president for research. "Very few safety technologies show this kind of large effect in reducing crash deaths."
It is true that SUV tends to benefit more with ESC because of rollover risk mitigation but the benefits to any vehicle cannot be downplayed. In fact, NHTSA has put in a mandate that all vehicles sold in US by 2012 has to come standard with ESC.
Here is the link to the NHTSA ruling:
http://www.nhtsa.dot.gov/staticfiles/DOT/NHTSA/Rulemaking/Rules/Associated Files/ESC_FR_03_2007.pdf
Mazda 5 is an excellent vehicle that fit my needs. Unfortunately, I decided against it because of the lack of ESC. Instead, I chosed the 08 Saturn VUE. My previous car (05 Grand Prix GXP), and my wife's (05 Pontiac Vibe) all have ESC. I can tell you, from first hand experience, ESC has saved us from some close calls. We live in Michigan and we have to deal with snow and ice. Sometimes, no matter how slow and careful you drive, you will unexpectedly hit an icy patch and lose control. ESC can help in these situations. Sometimes, it might not be life and death accidents but still in the middle of winter, any minor accidents with your baby in the car can be troublesome. Calling the cop, waiting for the tow truck, getting a rental car,....etc
Be careful though, having ESC doesn't mean you can drive recklessly. You still cannot defy the law of physics. It will not save you if you drive too fast for the road conditions.