I also thought the road test of the BM and the Merc was good, the camera work was brilliant. All in all, a great episode.
Can't fault the post work, though Autocar TV's pastiche of it was bang on. 😛
I'm surprised the Merc dropped the M5 that easily, AFAIK both put out 507bhp (Though the M5 is often quoted as 500 (though the actual output's probably being lost in a blur of PS equations 😛) I'm assuming it was from a rolling start where the extra torque and kickdown gave the Mercedes the advantage.