you are driving a truck that is at least 2000 pounds heavier than your old sportwagon. You have to expect some difference in stopping power.

you could try the porsche cayenne brakes, I don't know really... I find the stopping power pretty good with the touareg even when towing a trailer.

 

A friend has the V8 TDI Audi Q7 who puts big KMs a year on that vehicle. After replacing the brakes and pads with OEM a few times he tried some after market brands recommended to him. After playing around he went back to OEM as they worked better in the long run than the others.
Porsche, Audi and VW spent heaps of R&D money to match the stopping power to these vehicles, do you think some after market brands would really be better? Just throwing that out for you to think over.

 

My old boss used to have the saying "You buy cheap, you buy twice".

I have been following this saying for the last 20yrs, and have never looked back.

It applies to not just automotive parts

 

Would the 6-piston calipers and rotors from the T2 V10 fit the T3? That would be a substantial upgrade, but still OEM.

 

There was a lengthy discussion about this previously. Maybe things have changed, but I doubt you'll get better braking feel with the six piston caliper based on that thread: http://www.clubtouareg.com/forums/f44/when-to-get-big-brakes-68521.html