Who makes a better peformance Benz. I'm looking at and E55 AMG. Base HP is 469, I seen a Renntech stage 2 put out 510 HP, with a 0-60 of 4.1. Brabus K8 has 530 HP, with a 0-60 of 4.3. Don't know why the numbers are so different. Does anybody have any info on these two?