The fifth-straight win put the Magpies second in the Championship table, and the Spanish manager is confident that his players are capable of further improvement even after knocking QPR for six.
"It doesn't matter if we score six goals," said Benitez.
"The main thing was to get three points in the end. The fans can enjoy this result for the next few days and it was important to keep a clean sheet as well.
"We can still improve because everybody was working very hard but always we can make some mistakes."