When it comes to choosing between the Yamaha R15 V4 and the MT-15, it really depends on your preferences and budget. The R15 V4 is the more powerful of the two, offering more power and torque than the MT-15. It also has a better top speed and mileage than the MT-15. However, the MT-15 is more affordable and offers more features than the R15 V4. Ultimately, it is up to you to decide which of these two bikes best suits your needs and budget.