Decided not to drive the Caddy or the Lexus, just based on what I've read, I don't think they're for me. I wrote the GT-R, 911, and Cayman off my list from the start since I need 4 seats (and preferably 4 doors).
I did test drive the AMG last night though. Nice car actually, I was more impressed than I thought I was going to be. Handling didn't seem that great though, seemed a little like a big car with a really good suspension. I could the spring rates were high, but the dynamics of the car just weren't there.
The V8 engine sounded nice - though not as nice as the S65, IMO - and offered nice low-end torque, but seemed to run out of steam after about 5k rpm. I felt little desire to run out the gears other than for the sound of the engine.
The interior was very nice, with great seats and good ergonomic controls (I liked all the useful buttons on the center console), but it didn't overly impress me. I hated the fact that a new nav destination couldn't be entered while moving.
What really killed it for me was the transmission. Even in manual mode it actually felt a LOT slower than my ZF-made auto 6 speed in the 335i. Shifts were NOT crisp and took a lot longer than I had hoped. Certainly to the point where I knew I was driving an automatic. The lockup torque converter didn't spend nearly enough time in lockup condition, either, because it's mannerisms were of a typical automatic a good deal of the time. If I'm in true manual mode, I like to feel the drivetrain lash when I let off the throttle under acceleration in 1,2, or 3 gear. The M-DCT is just perfect.
So I guess that answers that. Like you all said, I'm glad I drove one though. Would have wondered if not.