Your are correct, Bosch has the contract for the 3.0 business and thereby has the dealer replacement business so it shows up in the parts books.
You are not locked by choice to go down that path nor on any other part replacement. The plug technology has moved on just as oil technology, tire tech, wax and the whole electronic world on since our vehicles were engineered.
There is no debate from anyone who understands engine management/plug technology that the four prong Bosch or NGK plugs will work as designed.
On the butt Dyno the fine wire ones will give you a smoother idle with 2015 gasoline and a cleaner tip in acceleration. Precious metal plugs has been around since 1985 when Champion introduced the H.O.T. Plugs. Bosch responded with multi prong as a marketing tool.
Update and be free!
__________________
2005 X5 4.8IS
The
Blue ones are always FASTER....
Current Garage:
2005 X5 4.8is
2002 M5 TiSilver
2003 525iT
1998 528i
Former Garage Stable Highlights
2004 325XiT Sport
1973 De Tomaso Pantera, L Model
1970 Dodge Challenger T/A 4 sp Alpine White
1970 Dodge Challenger T/A 4 sp GoManGo Green
1971 Dart Sport, “Dart Light” package
1969 Road Runner 383
1968 Ply Barracuda 340S FB Sea-foam Green