When you should use lossless compression
If you want to create a high fidelity digital archive, a better solution is to use a lossless compression format.
These formats work more or less like ZIP compression; redundant bits are taken out to create the compressed file, which is then uncompressed for playback.
So what you hear has exact fidelity to the original, while still being stored in a smaller-sized file.
Of course, a lossless compressed file isn't as near small as a file with lossy compression. While an MP3 file might be 10% the size of the original, uncompressed file, a file with lossless compression is typically about 50% the original's size.
This is why lossless compression isn't recommended for portable music players, where storage space is limited.
If you're storing your CD collection on hard disk, however, it works just fine—especially with today's cheap hard disk prices. You can easily store 1,000 CDs on a 300GB hard disk, using any lossless compression format.