Hi Grumndriva,
my real world experiences
I towed a 3t loaded off road van to alot of remote spots in my D3 (remapped to tow), and around oz as well (40k towing total). No WDH, no problems. Fuel range is a worry, but was not a problem, use to work on 450k a tank, and I have kayak, surfboards and 2 spare tyres(tyres only) on roof.
Now have had D4 3lt for over 12mths , towed same rig for awhile and range was 500k (3lt and gearbox are better),just in case I carry 2x20lt jerry can on van.(only ever used 1 can)
Have sold van and now tow a KK Karavan loaded 2t (they go just about any where the car goes), had a bit of van sway once , had come outof a track and was too lazy to change EAS rods for short hiway drive, so was in normal off road height and doing 110kph, but trailer assist was pulling it back into line.

I was a Toyo man for 20yrs before the D3, and have now got a D4, I'm happy with them

The adjustable height is great for overnight stays, you can always get it close enough, I don't worry about jocky wheel.
Dealer networks are a problem with all modern cars, seemed to happen when they stopped being mechanics and became technicians
Its a hard call and alot a money, go with ya gut feeling.
Cheers Ken
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