LowTech

Hi - Just got an S63 w/ 20" Pirelli PZero's. The sticker info on the car sort of contradicts itself on recommended pressures. The Driver door B-Pillar says one thing, while the fuel filler door says another. Here's the scoop:

Front: 255/35 ZR20 XL --- Rear 275/35 ZR20XL

The Driver door B Pillar sticker reads:

Front: 42 PSI / Rear: 44 PSI

But... The fuel filler door reads:

3 Passengers - Front: 38 PSI / Rear: 38 PSI
5 Passenger - Front: 42 PSI / Rear: 44 PSI
(Warm tires up to +4 PSI)

This is quite a variance and almost contradictory.

My question is, what would be the optimal tire pressure on my S63 given an average of 2 passengers?

Thanks in advance!