New Car Blues

My new Solstice GXP is in the shop. Seems there is a problem with the electrical system that they are having to track down. I was driving it the other day and starting to really get on the turbo when the traction control started braking the wheels and I got a ton of messages on the display: Service ECM, Service Traction, Service ABS, etc. I was able to limp home. I made an appointment with the dealership where I bought it and dropped it off on Wednesday. This is what they've done so far.
The diagnosis is still generally vague. At first they thought it was a grounding issue. They did find a loose ground and tightened it. That didn't fix the problem. Now they are going to replace the alternator. They think it was providing double current to the power board. They don't want just any alternator. They want one off the assembly line from GM (and I agree). Unfortunately, with "just in time" parts suppliers, that means ordering the part and waiting a few days for it to come in.
So in the mean time, I am driving a rental provided by GM through Hertz. No cost to me except for the fuel. I got a 2007 Chevy Impala. 89 miles on the odometer. Nice car. 6 cylinder with 300 horsepower. Not as fun to drive as the Solstice, but it will do.
More on this topic once I know more.