We had the top of the line Trailblazer LTZ. Single worst investment we made in our lives, electrical problems all the time. Windows that would fall down inside the door. When you needed the windshield wipers the motor would die or an actuator or some other component(three times diffrent pieces went wrong) When we needed to engage the four wheel drive, twice for road situation in winter would not engage. Problem with electronic activator and the second time some servo motor in it, they tried to say it was not a covered item on the warranty. We refused to pay them and I started raising hell in the dealership waving the bill in front of the customers in there talking loudly about how they are screwing us. Bill was paid for by them. We sold the truck for a big loss just to get rid of it.
We bought a Honda for her. The service has been phenominal, twice we had some not their fault with something wrong on it and dropped it off without a appt. and both times they spent time pulling something apart to help us out and called us up to pick up and no charge. Warranty items are not even discussed, just repaired. Of wich there have been only minor items not vital to the war effort.
That is why I don't buy GM anymore, three vehicles and three headaches, bulls!t problems and piss poor quality control. And three different dealers and all three smile at you while sticking it where the sun don't shine.
There, its off my chest and in answer to your question, IMHO do not buy one.