I have read that the Turner kit is solid. However that avenue will more than likely require you to foot the bill for the service and installation. I can only speak for my own experience which was actually very smooth once contacting BMWNA.
I first forwarded a letter explaining my situation, as I had been noticing the strange "popping" sounds coming from the rear exterior of the vehicle when reversing or when driving up or down inclines/driveways. That was followed by progressively unstable driving characteristics, the machine started to feel as if it weren't making solid contact with the road at mid to high speeds (mostly highway), almost like the back end was stepping out & sliding slightly.
I did TONS of research on this over the web and in many of the forums, which led me to first writing in to BMWNA, then following up with a call. I was contacted by a couple of reps that were more than helpful in getting everything arranged. I set up an appointment with the local stealership, and my machine was inspected and diagnosed with the broken subframe. They forwarded the details to BMWNA, who then shipped the new reinforcement to the collision center of my choice.
After about a month, got my machine back and that was pretty much it. There are a bunch of people who have experienced this and many still talking about it on this forum and others. Not everyone has had a positive experience, but I can't speak to the details involved in those situations.
Don't mean to hijack the thread, but just search for "subframe" on this site or any other owner sites and you'll find more than enough info. Yes this issue is a crappy blot for the brand, but it is fixable. And doesn't really speak to the overall build quality of these machines.
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