[Qsilver7]

In regards to the V8...the N63TU/TU2/TU3 are less prone to many of the horror stories you hear/read ...so if looking at the f12 650i or ix...then you'd want to look at the 2013-up model year in the US market to get eh N63TU engine. The first two years of the the f12/f13 (2011/2012 ~ vert/2dr coupe) have the original N63 engine. The roll out of the N63TU engine wasn't evenly distributed...the 5 series and X5 got the N63TU in the 2014 model year...the 6 series, 7 series and 5GT got the n63TU in the 2013 model year (see chart below).

If technology is your thing...then the 2013 model year had the CIC...and the 2014-up have the NBT iterations of iDrive (ID4/ID5/ID6).