I had a '99 540i. It was definately recirculating ball. The 528i I test drove had better steering feel but I prefered the power of the 540i. When switching to the M5, it was a noticably quicker ratio and the sport button gives more weight to it than any situation in the 540i but road feel was similar. The 545i and 550 are rack & pinion.Jayson said:It don't fit, but the 540 has a R&P, this could all be found under the search tab.