This will probably come as no surprise to people here, but I've just realised that for exactly the same part I've been paying around 20% more at an Audi stealer compared to a VW one. The similarity between the MkIV and the A3 mean that you can easily compare.
Audi want £99.85 for an amplified bee-sting aerial base, VW charge £59.75 for exactly the same part. An engine support arm (dogbone support) is around £50 at Audi, but only £37 at VW. The item codes again are identical.
Next time the car is in for a service I'll ask them to buy the parts from Citygate VW across the road [img]/ubbthreads/images/graemlins/smile.gif[/img]