But is it really in trim?

To answer your question we need to know more about the airplane model and radio. Then what is your expectation and level of experience. While a basic trainer might be trimmed out enough for basic flight, a more advanced model may take 50 flights to really trim out. There are so many things that matter so some degree that most never get to or are aware of. Today's powerful computer based transmitters and gyro stabilized receivers can mask a lot of deficiencies, but it is still best if you learn the basics.