You are ignoring the fact that OPV was used in the US from 1963 until 1990. Because it worked better. The choice of which vaccine to use depended on whether wild polio still existed. In the US it didn't, because OPV worked so well. Not the same in all countries, some of whom still have wild polio.

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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