On Feb 6, 10:34*pm, binks wrote:

Yes I too would be interested in what improvements are made with the
added winglets. One of the 20B's I am considering has the aftermarket
winglets added..still 15m ship after winglets were added.

The only thing you'll notice unless you are racing "Nascar style"
close is an improvement in handling and stall/spin behavior. We're
talking about an improvement as measured in average cross country
speed of about 2%. Flying for fun, that 2% is pretty meaningless.
But in a 15m contest, the difference between a factory original 20B
and a 27 is about 3% (at least the CH handicap for sports says so)...
now you get the picture.

-Evan Ludeman / T8