Having arrived late to this discussion, i beg the forum's pardon for any redundancy in my reply. Having moved from VW to BMW a mere 3 years ago, with an E-36 in ITS, let's suffice to say that I've learned a few things about these cars when raced. The most important of which has been that the guibo, a new guibo, coupled to a fresh and balanced driveshaft assembly, can and will come apart at random, attempting to cut the car( and driver) in half. Therefore, and based on the fact that no performance gain is netted by changing it, when I find an aluminum replacement for my application I WILL install it, and take my chances at the tech shed, where the downside is far less harsh than the alternative. Until then, an oil change includes a guibo, and fingers & toes remain crossed.

Sincerely, David Leira