What harmonica should I buy? (Key of C)?

The Special 20 is definitely a favorite for many people from beginner to pros. It has a plastic comb that will last longer while keeping a more defined tone and is designed for easy play. The Blue Harp is also great. This one has a wood comb which I prefer for tonal qualities that develop over time and the reeds are structured differently to keep more in suit of the blues sound. hope that helps.