I haven't been nearly killed by a German driver yet, and on purpose, and German drivers had many more opportunities to do so than American ones. But yeah, my impressions are of course only anecdotal, but then again, 100% verified from my perspective.
Autobahn-driving can definitely be nerve-wracking if you're not used to it, being flashed to change lanes when you're already doing over 150 k/h is quite disconcerting to say the least! But there is at least a system to it, and on regular roads Germans seem to drive pretty sensibly.