I use the Castrol 10w60 in my N54 too, but I take mine to the track every now and again so this oil should protect it better at high loads, rpm & heat. When the car was newish it used a bit of oil. Doesn't appear to use any/much now. Not sure if it's because things are bedded in better (now at 22K) or because I run 10w60 instead of the 0w40 I used to run.
Driving - Man 135 (LeMans/Black). BMW Perf SW & SSK. Quaife LSD, KW V2s, Ground Control camber plates, M3 front Control Arms & SB, Helix IC, AR DPs, PROcede V5, ER CP, Forge DVs, BMS OCC, Setrab OC, P3 Gauge.
Riding - ZX14R Kwaka, Avanti Aggressor, Malvern Star Equipe, Mini Mal.
Proudly from the Shire.