Wheels for A8 and V8 8x18/9x18, wheel configurator

Hello.

I just ordered new rims and wanted to ask, or someone has experience with these rims.

Currently I have the original Audi 7 star rims 8x18 ET 48 with 245/45R18 front and rear (see photo).

But since these rims don't look so full, especially in the rear wheel box, because of the press-in depth ET48, I have ordered rims in 8x18 ET 35 for front and 9x18 ET 35 for rear by ASA, which build very similar rims under the license of BBS (are also cheaper than BBS).
I can then continue my tyres 245/45R18 at the front and back (they are only 1 year old and 20 TKM old). At the next set I can also have 275/40R18 raised at the back (of course new registration necessary again).

Now my question: Has someone ever driven these rims and experiences with them or. Does anyone know if something needs to be changed at the rear of the wheelhouse at 275/40R18 to 9x18 ET35?

By the way, I found a great FELGENKONFIGURATOR for all cars on the Internet. In this link, my future rims are configured on my Audi A8.

http://www.bmf-gmbh.de/cgi-bin/goodyear/fr_assembly.pl?PKWN=0016&pkwBrand=Audi&pkwModel=A8&Image=audia8&ImageText=

Thank you for the information

Martin