A lot depends on the style. Howard Levy recommends the Special 20 and I don't think
anyone would argue that he's not one of the leading ten hole harmonica players in the world.

The Marine Band is the staple but I think you need to study the style of the harp players
you admire and find out what they use.

The difficult part of playing this style is "overblowing" for chromatic notes. Howard Levy
discusses this. He files his reeds with a small file to loosen them. I have never been
able to master overblowing. Joe Fillisco of Chicago (from the Old Town School) knows how to do this and has had harps for sale that have been adjusted in this way.

Many of the Chicago blues stylists don't employ overblowing techniques. Chromatic overblown notes are not needed for many of the blues pieces but bending the notes
which is more of a basic approach is necessary to get the flatted 3rds, 7ths, 5th's and 6ths of the blues scale.

I agree that the Special 20 would be good although Marine Bands can do the job too.

Frank