Benitez terminated his contract by mutual consent in December after lifting the Club World Cup and Italian Super Cup, making way for Leonardo.
"When I was at Inter, they refused to buy any players," Rafa told LaInformacion.
"After my departure, they brought in five or six new faces. Yet I won two trophies, including the Club World Cup, which was the one Inter wanted more than any other.
"It seems to me that my time at the helm was still positive."
Benitez also took a sideswipe at predecessor Jose Mourinho.
"He's a good manager, but I prefer the Spaniards like Pep Guardiola, Luis Garcia, Emery, Garrido and Caparrós."