Bmw does not SAE certify their cars. The A8 transmission in the ss and vette is extremely efficient when it's not overheating. It is not underrated at all.
I had trouble the first week of owning my 5th gen. After that visibility was a non-issue. I have no trouble at all. Of course I am 5'10" so that could be part of it.
I keep skimming Camaro6 and am noticing that they have pictures and video of 3 different HiPo Camaros testing at the ring. If the Camaro is at the price level it is now it will be interesting to see at what level they price these high performance variants.