FINALLY!!! Here are photos of my new 1-1/4 receiver hitch and removable bike rack.
I've been planning to get this done for some time. Since I ride alot (several times per week for the past 4+ years), it is worth it to me to invest a little extra in a good transport system. I tried the BMW roof rack but the appearance was too drastic. I considered a Saris trunk-mount rack, but I don't like that it contacts the paint. So, I decided to go again with a hitch and a hitch-mount rack. This is the most sturdy, reliable option and doesn't touch the paint at all. I can put it on and remove it in about a minute, in less time than it takes to put on a trunk-mount rack.
I have to give Master Hitch due credit for the great install. I have had Master Hitch install a hitch on my past 5 vehicles (including a few Audi A4). There are alot of car-specific hitches available in the aftermarket. Unfortunately, the Curt brand hitch for the 325 is tailored specifically for the 325xi (the all-wheel drive model). For some reason, the bumper area of the 325i (2-wheel drive model) is a bit different and the stock Curt hitch will not work on the 325i without modification. However, Master Hitch is a great company with some good talent working for it. So, for a few hours labor (around $170 with tax), they modified this Curt hitch to fit the 325i.
Incidentally, the Yakima Double-Down rack costs about $200. The Curt hitch retails for around $300, but I found one on eBay for less than $200 delivered. Total cost for this "project" including hitch, labor, and rack is around $550.