No benefit on a naturally-aspirated engine, IMO. You risk not passing emissions tests. Any performance gains are miniscule. This is particularly true of anything costing $150.

On the other hand, with a forced induction engine like the 335 there are benefits to be had, with the associated possible complications with the manufacturer's engine warranty.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue