It is a $40,000 vehicle, so I wouldn't go cheap (what if you burn out the whole circuit board?).
Personally, I would buy just one OEM bulb and see how things look.
I am fortunate to have unique press cars delivered weekly, but I own:
'16 BMW X5 xDrive35i M Sport 8AT
'15 Volkswagen Golf TDI 6MT
'86 Porsche 911 Turbo 4MT
Gone, but never forgotten... my E70 X5 35d, E90 335i, E46 330i, E36 328i, E70 X5 3.0si, E53 X5 3.0i.
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