Used to tow my osprey with a 1.6 renault estate, would agree a bit of rope gets you out on all but the steepest slipways although I did go through a couple of clutches.
Main problem I had was stopping, overheated the brakes once and nearly ended up on a roundabout on another occassion. Put the boat on a weighbridge and you will probably get a fright! Really should have brakes on the trailer.
I now run an old discovery which makes life a lot easier but overkill most of the time, stops well though!