Currently using 5w30 Quantum Longlife III oil in the A3. I used this oil in my MY06 MK5 GTI and got on very well with it, so it's tried and tested in my eyes (being Castrol oil, re-branded & VAG approved of course) .
The only thing I've noticed with the TDI compared to the GTI is that it takes around three times as long to warm up, for example I can drive over 8 miles of national speed limit roads through autumn/winter before the car reaches 90 degrees (half way on the temp needle).
The general rule is I won't exceed 3k revs until the temp needle is halfway on the dash, purely out of habit and conserving the engine - something I've always done in any car I own.
Is there perhaps an approved grade of Quantum oil I can use that will allow the car to warm up a little more quickly, without applying excess wear to the engine components?
Cars an MY10 A3 BE 3 door 2.0 TDI 170ps.