Choice of the rudder is very individual - both by boat and sailor(his technique). In South Africa they tested both blades - Blade 1(NACA) and Blade 2 (Steiner). So they had an opportunity to compare and choose the most appropropriate blade for their needs. From that moment they only ask for Blade 2. I got the following feedback from class association president about blade tests(quotes):

"Over the last number of years I have experimented with various rudder shapes and obviously re-invented the wheel! - your blade 02 is VERY similar to my most successfull shape. Since we added asymetric spinnakers to our boats we encountered a great deal of lee helm downwind. This I rectified with adding more mast rake but encountered too much weather helm upwind - kicking in the rudders solved this but left the blades weak because the tips were ahead of the pivot point and would snap if the weather blade left and re-entered the water. Thus the 'curved' forward kicked leading edge was my next option and this worked well!!"