So whats the best?

I know this will be opinion based, but here is the questions.
Which TDI motor is the best?
I own a ALH and my wives car is a BEW!
But she is wanting newer?
The next question which is the best auto trans?
Im looking at possibly 2010 threw 2015?
Unless I can find something the government does like? LOL!

IIRC the only auto available is the dsg. Plenty of info here about them.

Define "best". They all have their good points. They all have their foibles.

AHU is the simplest. Then ALH (variable-vane turbo), then BEW/BRM ("pumpe-duse" injectors). The common-rails 2009-onward are extremely complex. The 2015 fixed some of the 2009-2014's issues.

Same order in terms of power output stock. Pretty much the same order in terms of power output with the same level of modifications done. Reverse order in terms of emissions. Reverse order in terms of noise. Reverse order in terms of refinement.

The cars in which the AHU and ALH were installed ... are all getting quite old, and that introduces its own set of headaches.

If you are looking at 2010-on only, all the automatic transmissions (DSG) are the same.

So perhaps a 2015 Tiguam?

So if you are saying there were issues with the 09-14, when did the EPA problem start? Have they gotten past that yet?
Personally I don't care and would not have an issue with owning one!