I drove both the 3.0 & the 4.8, back to back, on extended drives. The 4.8 has a nice growl, but I was really underwhelmed with its performance. I guess I was expecting it to be similar to the E53 4.8is...I did not find this to be the case. The 3.0si seemed to have plenty of torque, and compared very favorably to the 4.8. I guess if you do a lot of highway driving, that the 4.8 is worth the extra $$, but I do mostly city driving, so the 3.0si is the better choice for me. The 4.8 that I drove also exhibited the hesitation from a dead stop that has been discussed by others here. The hesitation was very annoying.