I test-drove one in November last year. Mate of mine had arranged a test-drive and I just went along for the ride. Halfway through, we swapped places and I drove it around for awhile. I've always been intrigued by the Tesla ever since I saw the Megafactories episode on the Tesla S(
https://www.youtube.com/watch?v=Tvh_brqMJgU). The demonstrator came around to our docklands office during lunch-time and we took off.
The car itself, I was quite impressed with. The acceleration was ridiculous, as to be expected. We were on the freeway and to demonstrate the acceleration, the guy told us to pull over to the right hand shoulder, come to a complete stop, and then punch the accelerator to see how fast it would go. I wasn't too sure about this as I was worried that we wouldn't be able to get back up to traffic speed on the fast lane of the freeway and cause issues, but soon as the accelerator was stamped on, off we went and quick! I liked the massive screen that served as the control center of the whole car and I didn't mind the interior finishing. I also thought that it was quite spacious inside, although my normal car is a relatively smaller SLK so anything would probably seem spacious compared to that. Several times during the test-drive, I had to be conscious of the speed I was at, as it was really easy to speed in that car and not know it. Thought I may have been caught by the speed cameras on the Westgate during one of those times, but so far haven't got any speeding tickets.
Range of the car is perfect for me, I only really do inner-city driving, with a trip to the outer suburbs once every couple of weeks, so the quoted range of the car would probably last me a month or just under on one charge. Definitely considering it for my next car, if I can afford it. I'm no eco-warrior so its not because of that. I just like the car

I also like the idea of practically no annual maintenance(ie. no oil changes, etc...) so thats a bonus for me.