Hi Nick,
I have a 2.2hdi 2001 vintage.
I found the car very soft on the back end and fitted the heavy duty springs they have mad some difference but I have found tyre pressure makes the biggest difference with a car full of git/wife/kids (well not so much kids now at 16 & 19). I have towed trailers with it and also our 2004 Bailey Senator Arizona this it seems to tow up hill and down dale without much problem power wise but the car can feel a bit vague on the rear at times with the van on the back, this only seems to happen when on the motorway.
Hope this helps a bit Nick.
Martin "E"