i like my 128 because i get to use more of the motor on a daily basis rather then 10% of the n54. especially cause i'd go mod crazy if i had an n54 haha. n52 has moderate tuning capabilities if you want to spend money. with bolt ons a stage 3 manifold and a tune we can hit about 275 crank 255 at the wheels.
3 stage manifold, Mapleridge headers, AA tune