The SE-R weighs 3900 pounds
The SE-R weighs 3900 pounds even before adding a 1200-pound battery pack (albeit, while subtracting some gas-related components), and thus won't hold a candle to, for instance, the i8.
However, there a number of 250-mile cars that will be competing directly with Tesla within the next 24-36 months-- specifically, the Audi Q6 e-tron, VW Phaeton EV, Porsche Mission E and the as yet unnamed car from Mercedes, as well as a Volvo and Aston Martin by 2019. And of course there will be a 200-mile Bolt and Leaf out 18 months before Tesla MIGHT have a Model 3 in production, and a 170-mile 2nd generation i3. Additionally, BMW will have an i5 plug-in hybrid around then that might offer as much as 100 miles of plug-in range plus essentially unlimited gas-powered range (with quick fill-ups, of course). And then one could argue that the new Volt (out now) makes more sense anyway than the Model 3 (or any other mass-market pure EV).