Erika T.wrote a review of Thule Mercedes Benz/BMW Specialty Foot Pack on February 1, 2012
I used it to carry two snowboards from Springfield, IL to Twin Lakes, WI and had no issues.
Unfortunately, locks for each foot will cost at least another $60. I felt super paranoid leaving it assembled in Chicago, so it was kind of a hassle to remove it and then put it back on again later.
The foot back, combined with the load bars and the snowboard clamps cost a pretty penny but I think it'll pay itself off in the long run. Before I bought my rack, I could only carry one board in my sedan's backseat and one maybe two passengers who would have to be renting, haha. Now I can carry two boards and 4 passengers. Ah! Convenience!