Dexcool is the right coolant if you properly maintain your coolant system. Or if you have the updated LIM gaskets. I'm gonna stick with this.....

This vehicle has a newly developed engine coolant. GM Goodwrench® DEX-COOL® was developed to last for 240 000 km (150,000 mi) or 5 years, whichever occurs first. Follow the instructions in Draining and Filling Cooling System. Make sure only GM Goodwrench® DEX-COOL® (silicate-free) or Havoline® DEX-COOL® is used when coolant is added or changed.