Fr. John Hardon has a wonderful article on his website entitled Conservative or Liberal Catholic.
I think his final paragraph states it quite nicely.
A question similar to those which began this essay was posed to a Catholic priest just recently. In response to the query, “Father, are you a conservative or liberal Catholic,” he replied, “I’m a Roman Catholic. I follow the guidelines of the Vatican.” The holder of the Petrine Office is the direct descendent of Peter to whom were handed the keys of the kingdom. His mandate is clear; our duty as Roman Catholics is to adhere to both the letter and the Spirit as the Holy Father delineates them for us, not pick and choose those aspects of Catholicism more to our liking. As 2 John 9 reminds us, anyone who “does not remain rooted in the teaching of Christ does not possess God, while anyone who remains rooted in the teaching possesses both Father and the Son.”