I have been pretty happy with Carhartts which I wear pretty much every day. I have worn the knees out of a few pair but like to think I got my money's worth before then. I do have a pair of Wrangler work pants with reinforced knees. They are pretty heavy duty, and probably wouldn't wear them out somewhere (at least my wife probably wouldn't let me...). I have a few things from Duluth I really like. I will look at their shirts based on input here.
I also saw these some time ago. http://www.leevalley.com/us/hardware...1894&cat=71948
Don't think I would spend that much on a pair of pants but they look pretty slick.