I have an Australian spec MY00 WRX. I've also just bought a 1989 Van Diemen Formula Ford with enclosed dual axle trailer. Together they weigh about 750kg which is exactly the rated towing capacity of the car. I've towed it around the block a few times but I have to hook up an electric trailer brake controller before getting any speed up. What I want to know is if the car can pull this kind of load without straining too much up hills, whether it will place undue stress on the drivetrain etc. I'm pretty much considering getting another vehicle as a workhorse, probably a 1996 Holden Commodore wagon, but if I can avoid it I will.

 

I have done a fair amount of towing with my UK Turbo Wagon.

Only upto about 500kgs with no brakes though.... and all has been fine.. It goes up hills without any problem..

The only two things you must be aware off are the weight limit of the trailer and equally the nose weight of the trailer..
As your trailer is a four wheel trailer the weight shouldn't be all on the nose. I believe the nose limit weight is 75kgs..
If you can lift the front of the trailer with the load on it then you are not exceeding 75kgs is how I look at it.
There has been rumours of the tow bars damaging the car and so you should inspect the mounting points regularly. I believe these rumours were started when dealers have been saying you must fit our tow bars because otherwise damage will occur and people have taken that for the truth. Personnally I have a tow bar put on by a speciallist.. no problems and I have done probably 5000miles with a 500kg trailer fitted.

Happy towing

JGM