In terms of mileage, power, comfort and riding skills.
If you are into race, super quick and can compensate on long rides then go for RC. RC 390 is hard to drive in city traffic. Whereas CBR250R is a complete package for City riding and touring with ease and comfort. Wait for new updated CBR250R, I am waiting for it too.
The KTM RC 390 is the best bike out of all the above. It comes with the most powerful engine, producing 43 BHP @ 9000 rpm and 35 NM @ 7000 rpm from its 373.2 cc. single cylinder liquid cooled, fuel injected motor. It comes with the most comfortable race position, making it a good choice to enjoy medium and high speed riding. It even comes superb handling and a very good built quality when compared to all the other bikes in the segment. The only field where it lags behind is mileage, but when such a big boost of power is delivered mileage is surely going to get down from a comfortable value. It return a 25 kmpl mileage, making it the best above all. It comes with a price tag of INR 2,12,000.