Hey thanks man! You know, if they made a dark green Fed IV I’d be all about that.C'mon, man, green hats are cool! But seriously, I don't know what kind of pollen or other contaminants are blowing around the suburbs east of Los Angeles but I've had my Dark Brown Fed IV for nearly 10 years and it's just as dark brown as it ever was. As was already mentioned, a good brushing now and then should keep your hat looking good as new.
I don’t have a hat brush, but have been using Sam’s old baby brush. It’s soft and works pretty well.