My first PRIUS 2008 GEN 2 had dangerous oversteer from battery weight in the rear. It could be pretty hard to control once it started to fishtail. In the rain one had to drive with extreme caution. My wife was terrified of driving it in the rain especially if the trunk was filled up with heavy stuff. I noticed I had to adjust to it after driving my other car because it had serious oversteer, now I understand why the Corvair had issues,lol.
Anyone else notice this? The new Prius I have the 2012 Gen 3 does not seem to have this problem. It has larger tires and it a bit heavier in the front.