I can create music, record it, add arrangements, mix it and master it to CD, all on the computer. For a true project studio with pro capabilities, you'll need to add a small mixer, an amp and some monitor speakers. A DAT recorder is also nice. When shopping for a CD recorder, the most important considerations are speed, buffer size and whether it has re-write capabilities. This is a great feature for backups or storing projects likely to require change.
Speed is a simple spec.
At 4x speed you can record a 650-meg CD in about 18 minutes. Buffer size is extremely important. The buffer is special memory built into the recorder that stores data until it is needed. If this happens, the recording will fail. Better burners have a buffer of 2 gigs or larger.