Forget the 2,500 km run in. It is quite likely that most engines have been on a test bed being run for a while before the car is assembled.
Mmmm ... that may be the case ... but can you be sure the engine you get will have been run long enough on the test bed

... the salesperson might tell you that you don't need to run the car in, only telling you to 'take it easy' for the first couple of hundred miles ... but will the salesperson's advice be the best advice to follow

... invariably they will tell you one thing when contrary to the facts they could easily obtain, it will not be the best advice they could give you.
By way of example ... BMWs 3.2 M power engine has to be 'run in' and the owners manual details the limits to be observed for the first 2,000km. Many 3.2 M power engines in cars whose owners thought along the lines of ... sod that I'm just going to 'give it some beans' after a reduced distance 'run in' ... ended up with the car back at BMW and the engine having to be re-built

... while this will obviously not always be the case ... would you risk it
However, with such a large investment of money ... I'll be double checking the book and guidelines laid down by Audi themselves ... not the salesperson. It won't hurt to run the engine in ... 'according to the book'. If you plan a weekend, or two, away in the UK ... you could easily clock up the required 'running in' distance in a couple of weeks. If you live in the South, take a trip to the Yorkshire Moors, or the Lake District. If you live up North, take a trip to the West Country, or South Wales.
Just my two pence worth
