if you are in Ontario you can try my speed 3 19m
i like it. They always have some tube kite that they say kicks ass in super light wind and they are just OK, the manufactures have been saying that same thing for 10 years every year.
the speed 3 has a bit more pull than my 2010 crossbow 16m which is a great low wind kite too.
if you want to try it sometime email me at firstname.lastname@example.org
it is not the end all be all but it is a great kite.
6 knots I don't think so but throw a few more knots in and you can mow the lawn.
it relaunches way easier than a big tube kite in low wind.
you must match it with a good low wind board like a door, wing, fish surfboard, skimboard e.t.c. for it to work in light winds.