I guess at the end of the day, it depends what you're looking for. I truly believe that most of the time, if you want the best, you gotta go dedicated. Otherwise that person is sharing their time and effort over multiple tasks. That said... I did say 99%. I didnt' say ALL. So there is a difference.
It's just my two cents
If I'm talking out of my 'artist' ass, just ignore me :P