According to the H&R web site, the Audi spacers are identical to the VW spacers.
Additionally, the Mercedes spacers ae listed as having the same-size bolt holes
as both the Audi and VW spacers.
So, at least according to the website, there should be no problem:

Spacer                   Bolt Pattern          Center Bore            Bolt Hole
VW (Passat)                  5x112                     57.1
14x1.5
Audi                              5x112
57.1                     14x1.5
Mercedes                      5x112                     66.5
14x1.5

I don't have any experience with them, just passing on the information.

Todd
'88 Westy

Ben T wrote:

> In a message dated 9/12/01 6:18:17 PM Pacific Daylight Time,
> Rubatoguy@MINDSPRING.COM writes:
>
> << http://www.hrsprings.com/fcgi-bin/query.fcgi/site/scripts/spacersquery.cfg
>  note - I was told the Mercedes spacers in the Vanagon bolt pattern will
> work. >>
>
> Todd,
>
> Keep in mind that most Mercedes cars have smaller bolt holes. A better bet
> would be certain Audi spacers. One problem with using H & R's spacers is they
> are hub centric. So if you are looking to get front dust cap clearance, it's
> a good idea to check how big that hole in the middle is.
>
> BenT