I owned a 2011 WRX hatchback for five years and loved the car. It did everything well and was a blast to drive. I've lived in New England for 25 years now and the WRX was hands-down the best car in the snow that I've owned. With good snow tires on it it was far more fun to drive on snowy roads than it was on dry pavement. Something about Subaru's differential setup allows the power to be driven to all four wheels very evenly so oversteer is incredibly predictable and you can steer the car with the throttle like no other I've driven.
The car was also really quick. 0-60 in under 5 seconds, according to the tests. I had a base WRX, for which I paid $25K new. It was fun, practical, reliable and an amazing value. It was not perfect.... It was loud. The wind and tire noise were much worse than a car should be in this decade. The stereo, and in particular the phone integration, was abysmal. Fuel economy was OK at best, I got 28-30 on the highway, and about 24 in mixed use.
The M3 is undoubtedly faster to 60. It is also a wonderful long distance cruiser, something the WRX is definitely not. But I'd argue that the WRX is more 'fun' to drive, at least on the street. All in all, I prefer to own the M3, which is why I no longer own the WRX. But they are great cars, and at times I miss mine.
I have been watching "Launch Control" about Subaru North Americas Rally and Rally Cross teams. I has made me consider if the Tesla would make a decent platform to build a rally car around. I think the motors and software would be terrific, you have the ability to really put power down quickly in a highly controlled way, and there are simply a lot less moving parts to worry about. Rallycross in particular rewards the best launches, and as most of us will agree, nothing launches like an electric. The battery is going to be the challenge. It would have to be really heavily armored or moved out of the bottom of the car, meaning that the Center of Gravity would go up, which is obviously not good.
There are already a few folks out there trying to build electric Rally Cars. Opel has announced plans to build and sell one, a relatively low powered version of its production street EV, and there is a Hyundai Kona (in name only) being developed in New Zealand that looks to be competitive with gas powered rally cars (300+ continuous HP, 800 peak HP). I'm sure it will take years before electric rally cars are a fast, reliable, and versatile as the current gas cars, but I believe that the tremendous low speed performance of electric, combined with the electronic power delivery aids (traction control, torque vectoring) makes their ultimate potential higher than gas cars. It promises to be fun to watch!