MP2 vs. WAV vs. MP3
The audio from Scott MP2's is significantly better than any MP3 if you're broadcasting in analog. In case you're not familiar with compression algorithms, MP2 is designed for video, and is a less lossy scheme than MP3. WAV is not compressed, and is better than MP2, but also requires more bandwidth for transfer, and more hard drive space for storage. The difference between original material stored as MP2 or WAV is not as you describe.
Of course, your original audio can suck before you encode it as MP2 or WAV. Also, if you're running digital, you're adding another layer of compression to an already compressed file. That can create artifacts and audio issues, which is why you want an uncompressed format for digital.
On top of it all, the crap that is coming out on CD these days has the dynamic range of a brick. Even if you rip it into a WAV file at a high bit rate (like 44.1K), with good quantization (like 16 bit or 24 bit), it will still sound like clipped and compressed crap because the original waveform is clipped and compressed crap. Radio stations that play a variety of rock music that ranges from the '70s to current have real problems because too many artist today want their CDs to sound "like the radio". That means that studio engineers add compression and clipping and a whole range of processing to the original CD sound. Add more compression and clipping and processing, and you get muddy bass, chopped highs, and lots of digital artifacts. Rip it into a 128 bps MP3, and it will sound like satellite audio, which sucks.