I was looking to buy a diesel Promaster a few years ago for my side business. I could not get past the 'feel' of the twin clutch trans. It's just odd. I drove three different vans thinking that the first two had a problem. Turns out that that is just the way they are. The ones I drove were shifting constantly around town and the auto clutch actuation was often times very abrupt so it does not surprise me that people are having issues with them. Imagine teaching someone to drive a stick and they insist on worrying more about fuel efficiency than smooth shifting before they really know how to let out a clutch properly. I've driven Fords and Mercs since then and they seemed perfectly normal in a truck/van sort of way.
You'll notice the rear axle does not provide much ground clearance also but that might not be an issue for you.
I never buy new vehicles because I hate paying money to do beta testing for someone else and there is really no way to know what the flaws are until they are in use for a while.
I have heard the same thing you seem to have heard about the trans not holding up.
Edited by roverjohn, 29 January 2019 - 04:44 PM.