I got the Thule hitch mounted one.....DOH. I should have gotten a Yakima one.

The Thule hitch one worked well, but a more cumbersome design than the Yakima one.

Of course, the hitch rack design can be different nowadays.

Anyhow, I haven't used a trunk mounted bike rack in years....I used to have one for my E30 3-series, but you risk scratching the trunk paint with either the bike or rack. I remember scratching the paint off the trunk lid spoiler with the bike pedals

Anyhow, since you have a S4 wagon, why not just take off the front wheels and load up the bike in the wagon portion?

I wouldn't risk a trunk mounted rack option on your M5 IMHO.

Anyhow, if you know what you want, here is a great mail order place for bike stuff (both Thule and Yakima stuff). No sales tax and usually free shipping....
http://www.ageebike.com/Opening.htm

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