An S2000 or modded Civic might do in the Brabus on an autocross in a parking lot, but on some real road, forget it. It can handle enough and once rolling, all that power comes in pretty handy for a 200km/h "ahh, see yaaaa." If you like crashing through 300km/h, the Brabus is one of the few that can do that, too.
The original "AMG" car (though not modifed by AMG, but by the engineers that would leave MB to form AMG) was the 300SEL 6.3. Same story. Stuff an engine from a big car into a smaller chassis and make it go REALLY fast. In it's day, that car was insanely fast. Heck, even today, it's a little shocking. Years ago I was out on an MBCA road run and I was passing a line of cars with the speedo reading 190. In my mirrors came a guy in his 6.3, reeling me (and everyone else) in. Not sure how fast he was going, but at 190 I felt like I was standing still. From a 70's vintage sedan? Yow!