Michael
If you want to cruise on the autobahn and make lovely V8 noises , then a +8 is hard to beat. (The 3,9 is fine , you won't need the extra torque of the 4.6) However if you enjoy more challenging twisty roads and more forgiving handling then the 4/4 is probably more suited. The modern +4 with Duratec or GDI engine falls in between the 2 .
As Richard says join the German club and try to get one of their members in your area to come along and inspect any purchase before you commit.
