Spark plug Bosch or OEM BMW

Your observation is correct.

Bosch is the original manufacturer. Buying from them will be cheaper. Mercedes genuine just means they take the Bosch part and slap their name on it to say "yes, this component is up to our standard".

I have a N55, e93 And went through the same back and forth between NGK and Bosch. My car is 100% stock. Ordered ZR5TPP33 Spark Plug - Bosch and the car runs just fine.

My F15 had the Bosch ZR5TPP33-S from the factory. I replaced with ZR5TPP33 when doing the valve cover about 20K miles ago, and no problems so far.

If you change the plugs; use the recommended plugs. I used Bosch Double Iridiums in my truck and they've worked good for 4 years now.

I just picked up 6 Bosch dual electrode double iridium spark plugs from autozone near me and threw them in. Fires great!

Yes. However as a long time old car mechanic I learned the hard way some new cars are super picky about what spark plugs you put in them. It kind of caught me by surprise. Parts store gave me Bosch plugs their system matched to my GF's Pilot, and it fell on its face hard about a half hour into the next drive.

I don't use spark plugs like that unless the vehicle specifically specs for them. We used to put Bosch W7DTC's in these, or at a minimum, just the single electrode version.

If it is the skyactive-x be aware that the owners manual advises spark plug replacement at 40k miles and the Mazda plugs are \u00a340 each. I put aftermarket Bosch plugs in and it ran very lumpy and had to replace with Mazda ones.

Cylinders 1-3 were misfiring. They couldn't get the spark plug out of cylinder 3 because the other dealership had over tightened it. They had to get a special tool to remove it. The tool BROKE because apparently it was so overtightened and mis-threaded. They finally got it out yesterday and sent the cylinder to the machine shop to get the head off. I just got word that there is a hole in the piston and the valve head is completely gone. They are saying now that it has nothing to do with the spark plug being overtightened. He asked about driving through water, and road conditions. It was a dry day. Not an issue. They said I need a new motor at this point.

My s2000 ate the Bosch plugs I put in, which were rated for the car/f20.