I have towed MANY motorcycles with my 2011 Golf TDi, with a lightweight trailer. I've towed 2 sportbikes on the same trailer for 10hrs, with all of our gear, generator, spare wheels and tires... Only had to downshift once for power, still got 35mpg.
Just have to be smart about braking and manuvering, plan ahead. I've never had a problem to speak of, but I have lots of towing experience with trucks.
I'm using the Curt hitch. I had to get an extended ball mount just because my car is lowered. Definitely plan ahead, my trailer sways a LOT with a cruiser on it, but thats because theres more weight on the back of the trailer. I'll post pics when I get home.