i have a 530, its cool I think but the extra torque and wheel spinning HP would be sure to raise a smile on your face. Nikasil isn't that big of an issue as long as it idles pretty smooth and starts easy. The M60s also have intake leak issues that have led to MANY replacements of the engine instead of isolating the problem. The intake leaks also will caus it to throw a check engine code which says O2 sensors, ICV does the same. Other than that the 540 supposidly gets better mileage on the highway than the 530.
enjoy !
95 E34 530I V2.37
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