I wouldn't stop using Dexcool. Just don't think it is okay to leave it in for 100k. Change it every two or three years / 50,000 miles. If you do decide to switch make sure the coolant you choose is 100% compatible. It will say so on the container. If it isn't, you are in for one helluva mess. Cause it is almost impossible to get all the coolant out of your engine.