You are just one of many who feel same way when they get to Germany. Want to rent a raicy car. They have a special going on for M3 cabrio (99 EUR daily if rented for 7 days). You may want to check if that is available...note km is limited to 300 per day.

http://www.sixt.de/top-angebote/

Sixt has 116i, 116d, 118i, 118d, 120i, 120d, 318i, 318d, 320i, 320d, 325i, 330xd

For VW Scirocco I have seen only 2.0 TDI