Good info.
I just rolled the dice between the N54 and N55 and my 2010 is on the boat with a delivery to me in 2 weeks. All the reading I've done on the new N55 doesnt impress me thus far. Alot more complication for what seems like same HP/TQ production. Minor weight savings, minor fuel economy(1 MPG better in one report I'be seen). And much more difficult to do power enhancing mods. And when in the future, after warranty is up Im thinking its going to be an expensive nightmare to work on. Right now Im happy with my decision but time will tell.