In 150 cc category CB unicorn 150 is the best with respect to mileage and performance. Recently I have bought a 2017 bs4 aho cb unicorn 150. It is giving a mileage of 50 km/ litre. My place is a hilly area eventhough it is giving great mileage. The black beast is a legend but it has some drawbacks also . Old design , no engine kill switch. Weak battery . No digital meter console. Poor seats. No rar disc brake. Excluding these small demarks it is the better option in this segment those who love long rides. Need heavy mileage and standard design.