Sorry about not being specific enough.
The brushes will be for general painting of aircraft, mainly WWII era. I already have an airbrush for overall finishing (although I may replace that too, but that's for later!). The brushes will be mainly for detail work, along with drybrushing and washes.
I've been pretty good at taking care of the ones I have, but time has taken it's toll on some. I've heard arguments of natural filament vs. synthetic, etc., so want to make sure I get good brushes for work. Brand names, like you've given me, are especially helpful.
Thanks again for all the replies!
Mark