V8 with a big single like n55. copy the bms stage 2 boost/fuel curve. As an n54 owner, I love the torque of the twins but the hunt for boost leaks is no fun. More turbos, more places where leaks can hide, and less room to work in the engine compartment. The n55 drives very strong stock as well. Cant Imagine what the V8 with a similar set up might be like. Add a nice tune to it and keep it simple.
If not, go with the twin V8 I saw in the X5.0 I saw today.
JB4 beta 15 ohms FSB,AEM inline filter/ CM 10, ETS fmic, ER custom made charge pipe,TSW Donnington 18's,Simitumo HTRZ3, Injen DCI, AR DPs, Forge DVs, AA SLD, Koni FSD, ZSP springs.