Kolinsky is the type of Sable used for the bristles. Da Vinci is
one brand of brushmakers that produce Kolinsky sable brushes, they are in my opinion an exceptional quality, however I have not used Windsor Newtons so I cannot compare. And I'm not saying the newer painters shouldn't use them, just be aware that they are less forgiving of bad treatment. In fact check this out, its long but research is always good if you don't want to waste money.
http://www.youtube.com/watch?v=eACqcAQdw2U Automatically Appended Next Post: For cleaning your sprue use warm water with a little bit of dish soap into it. The soap needs to have a degreasing element to it or it will not break down the release agent. And as I say insure that the water is warm and not hot so as to not warp any of the components.