I want to buy a bike which gives high mileage and good performance?

Boss, high mileage and good performance are enemy of each other. A bike that gives high mileage will not give High performance and a bike which gives high performance will not give high mileage. So you have to decide whether you want high mileage or High performance. If your priority is high mileage, buy a TVS Star Sport. If your proirity is high performance, buy a Kawasaki Ninja 250R.

dear ravindra go for only PULSAR 200 NS

It all depends upon the price ur willing to spent for the bike