Audi need to up their game in the 2.0TDI range, and release this twin turbo 2.0 tdi cr thhat VAG are supposedly developing.
BMW have had their 201 bhp twin turbo out for a while now, now Merc have released theirs, both leave the 170ps 2.0 CR well behind. Having a similar engine in the A3 would mean you'd miss that ST-3 performance much less, so looks like a remap would have to suffice.