This is definitely a good read for me, currently on the fence whether to go with a late model E9x or an F30 model. Currently the price is a big of a factor but the longer i wait the more ill have for the newer model, unless there isn't that much of a difference. In either case both would be a 335Xi M-sport packages.
From a little research it is obvious that the N54 motors have a lot more tuning potential, just looking at the accessport dyno's the difference is unreal. Definitely is a mod that i will be doing on what ever model i get.