From the dBpoweramp site
"Compression affects how much effort goes into compressing the audio, all compression modes give the same decoded audio (it is lossless after all), the higher compression levels will give a small % file size saving, but will require more time to compress and decompress. Compression Level 0 requires the least compression time, whilst Compression Level 8 the most. Uncompressed is a special compression mode with stores 16 bit audio in an uncompressed state."
So, uncompressed sounds like the best for 16 bit data, although I have never tried it.
No experience with EZ CD Audio Converter.
"Compression affects how much effort goes into compressing the audio, all compression modes give the same decoded audio (it is lossless after all), the higher compression levels will give a small % file size saving, but will require more time to compress and decompress. Compression Level 0 requires the least compression time, whilst Compression Level 8 the most. Uncompressed is a special compression mode with stores 16 bit audio in an uncompressed state."
So, uncompressed sounds like the best for 16 bit data, although I have never tried it.
No experience with EZ CD Audio Converter.