E55, patience, my boy! I have driven more Mercs, than most. One of my test cars, (actually a normal E500) suffered an "interesting" SBC failure three times. And yes, even after software update. Funny feeling, especially on a track at the end of a straight, believe me that. And straight line performance is not the whole picture. Your SL65 goes like hell, but which biturbo V12 doesn't? The E has good body control for the street, but terrible on the track. Wallowy, have NO diagonal damping. And in some turns the steering has awful kickback. Seriously, I met a journo fellow who didn't dare to sit in an SBC-braked Merc.
Ah, and one SL55 AMG had the same problem when creeping to a parking lot at 10 mph! After update, the problem disappeared miraculously. Indeed, the very same car needed a laptop, some additional wizardry and two further hours just to be able to close its top. But the SBC was/is the main issue; that's why MB recalled all of their SBC-equipped cars...
For me, no Stuttgart Stars, thank you.