I finally figured out how to upload MP3's. Afterwards, I did a quality comparison between a few clips I converted to WAV and MP3.
Settings on audio files to upload to phone:
WAV = 8000Hz, 1 channel (mono), 8 bit
MP3= 8000Hz, 1 channel (mono), 32 bit
If any of these values are increased, the upoad to the phone will most likely fail.
The MP3's were smaller in file size (almost half), however, the WAV files had slightly better sound quality for the phone. The WAV files were louder in volume and filtered out a lot of the high frequencies, which can make the ringtone sound a little distorted. You can also compare footprints using the Audacity program.
It's really up to the user - quality or quantity.