MP3 vs M4A: Which Should You Download?

Choose MP3 for old car stereos, basic players and anything you are unsure about. Support is close to universal.

Choose M4A for phones and modern computers. AAC usually sounds as good as MP3 at a lower bitrate, so files can be smaller. iPhones play it natively.

There is no point in converting M4A to MP3 afterwards, as each lossy step loses a little more.