Also, note that if your sernsorValue is exactly 100, 200, 300, etc, it wall fall through to servo1. Which is probably not want you want.
typically you would code more like
else if ( 100 <= x && x < 200) ...
else if ( 200 <= x && x < 300)
the main point being, that on one end of your range you include the "endpoint", and on the other end you exclude the endpoint.
Cheers,
John