Martin,
It towed fabulous! I hardly knew it was back there! Only the little bit of orange roof in my rear view mirror gave it away. It tracked right along. I think it accelerated a little more slowly but I never really stomped on the gas either. With the 454, pressing down hard on the pedal can consume a gallon of gas!
I did not notice much difference in braking either.
The biggest disadvantage, other than the face that the car is 41 years old, is that the two bar requires you to get on the ground and reach under to put in the pins. It can require a towel since you can get a little dirty. The other challenge is what to do with the tow bar when not connected (home and campsite). The price is right though! $110 as opposed to $400 tow hooks and a $1,500 tow bar assembly!