Ampera aka IGOR
Do you know what the diagnosis was? Mine has developed a bit of a noise getting the wheels refurbed and two new front tyres. It hasn't been the weather up here for me to investigate. It does it all the time, speed related, but not as loud or course sounding as the main bearing clips I have seen. It's not as high pitched as a wheel bearing and braking does not stop it.Just for general info re whether or not to drive with the buzz saw noise, when I bought my Ampera last year at 80,000miles it already had the noise (which I mistakenly thought was an electrical buzz, not having any previous experience of the cars) and I did over 2000 miles before getting it fixed. It got a bit louder over that time, but the car came to no harm.
It was fixed willingly under warranty, much to my relief, by Pentagon in Sheffield.
And yes, I've had 2 failed charge leads, the steering lock hassle and a failed wheelbearing too since then!
Still a very nice car though.