Can you tell me how you drive it manually? I have a DSG and tow a small van. I've never driven it manually but it would have been useful to be in a lower gear than the engine thinks as I can see the road!!If it's a big van (mines 1900KGs) and you load up a lot in the T6 then I'd go for 150 rather than 102. Like many I take way more stuff than is needed camping.
I have DSG and drive it manually when towing as it's rare for me to get into 6th let alone 7th gear. At 56mph it's usually happier in 5th. I suspect a 102 wouldn't get out of 4th except downhill.