Chronic head gasket failures (twice in the 20k miles owned).
Electrical bugaboos (gauges don't work properly).
Engine sometimes overheats on mild uphills (probably due to lack of power).
Needed new transmission on purchase.
Stalls quite frequently if not started at least 2-4 times per day.
A/C does not work.
This vehicle is very slow to the point it's almost a hazard. My 1994 Toyota Truck 4x4 xtracab, even with a 4-cyl, accelerates like a turbo MR2 compared to the van.
The van is roomy and very comfortable and is great for camping trips with the pop-top. That's the only plus about the van unfortunately.
Due to its unreliability, the vehicle has been relegated to recreational status until a more permanent vehicle can be obtained. Might get a Toyota Sienna or Highlander to replace it.
I can't say their perfect, and overall agree that the wasserboxer motor is not a good choice (I am using an 89 Jetta motor, much better).
However;
A.) You can't blame the tranny on the van, earlier trans had some issues/bad sliders. That was fixed by then. Purchasing a used vehicle and complaining about an issue you didn't spot is rather silly, and much like sour grapes.
B. Engine issues with the wasserboxers. The specification calls for non phosphate coolant. If you don't use it the heads erode. If you do so they do O.K.
Overheating. I'm not surprised since he seems to go through heads.
Overall they're far from perfect, but as with all vehicles you do much better if you Read the Manual.