Once you own a collection of boxes, as one inevitably does after a few decades of fly-fishing, it becomes quite difficult to justify buying a new one. I drool over boxes in shops regularly. I turn them over in my hands. I stand there in the shop, thinking  that if I bought this one, I would use it for my Caddis & Midges, or my general purpose river nymphs, or some such thing. Then I put them back, and move on. Because you see, at home I have whole collection of perfectly good ones.