We have just taken delivery of our first van, a Coachman Amara 550/5 (~1350 MIRO, 1550 MTPLM). We are pulling this with a VW 2002 Sharan 1.9TDi 15 hp(no engine tweak/mods/booster etc.
So far on the way back home from the dealer with the van on the back (distancae ~ 15 miles)with some hill starts at traffic lights, car pulls fine. When we have the van loaded up with all the stuff for our fist outing we expect to exceed 85% ratio by a small margin. I'll probably post a summary of my first ever adventure at a later date on a new thread somewhere.