My height is 5.7. Is it comfortable for me to ride the KTM RC 200? And is the light weight alloy wheel of RC safe?

You would not be that comfortable in riding the KTM RC200 but it won't be even difficult for you to adapt to the seat height and handling of the motorcycle in the traffic. The lightweight alloy wheels on KTM bikes are made up of excellent metallic compounds but are actually not made to resist the potholes and sudden high speed jerks. The suspension on the other hand again has limited travel and riding the bike on rough roads can increase the chances of accident due to some stone bouncing off.