Originally Posted by Penguin

Reliable and smooth.

I'm not saying the V=8 is not an excellent engine, just the the six has had better reliability and is inherently smoother by basic configuration -- a straight six is inherently better balanced (which, IMHO, matches my test drive experiences.)

P.S. If you have a chance, talk to an experienced BMW mechanic that works on BMW engines and ask him about straight 6 vs. V8 reliability.