So every review I’m reading seems to think the s63 is the long awaited breath of fresh air to replace the old aj133 which came about 13 years ago in 2009.
You read about the new defender and people say things like it should be the BMW unit they are just using up all the remaking 5.0 units.

The thing I can’t get my head around is this is being touted as a new great engine, but it’s not new it was first put in a car in 2009 in the x5m… so I’m trying to work out why they are replacing an old engine with an old engine when BMW are shortly going to release the S68? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

usual press release hype pal , most will buy it , hook line and sinker

M engine maybe for svr if any.. L460 will have N63. Both great engines until warranty is valid and if you like check and add oil regularly.

I believe the n63 is actually a year older 😂 Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Just and only engine wise it was similar situation with L322. M57 and M62 were replaced/upgrade less than year later on BMW range.
N63 has always had troubles and problems. It’s been updated tweaked few times but no big difference in terms of reliability- if you speak with mechanics and not with first owner.