Sorry, I came into this thread a little late.
The only input I will put into this question is:
DO NOT TOW ANYTHING WITH A V-STROM
I would refer you to the owner's manual. It wasn't made for towing, it isn't allowed by Suzuki, and there is no provision in the design for towing. Gold Wing is the only motorcycle I know of that is spec'ed by the maker to pull a trailer, and I don't even recommend doing that.
From experience I know that plenty of you are going to come back with "but I have been towing with my _____ for XXX years and never had a problem, etc etc etc." "It'll never happen to me." Or my all time favorite:"I'm pretty smart and I figured out how to put a trailer on safely"
I am a professional collision investigator, and I attend serious crashes on a daily basis. I've seen home built trailers, commercially built trailers, and even a old whiskey keg made into a motorcycle trailer.
By adding a trailer to a STROM you are creating a double-articulated vehicle, with at least 50% more weight in the back, and no brakes on the last axle. When the trailer weight shifts onto the rear bike wheel, bad things happen. Generally when a motorcycle tries to emergency stop while trailer towing, the vehicle tends to swap ends, the bike falls over, and people get hurt. That's when my phone rings.
Gentlemen, (and Stromette) Don't do it.