Lovely wings... After studying your wing tutorial and other people's work with wings I think I'm going to make a pair of my own with a few slight modifications to the style. Your tutorial is probably one of the most useful ones on the whole internet by the way. Not to mention you look gorgeous with them on.
Durability depends on the wire you use as a base. I used wire hangers, so its' fairly durable, but pretty bendable, if you want more sturdy wings, probably use a copper wire.
Hours-wise, I'm actually not quite sure It took me roughly a month to make these (one or two hours a day), but I also trimmed feathers as I lay them instead of doing it ahead of time, so I suspect that was more time consuming than needed be. It also depends on the SIZE of the wings you want to build. Just to be on the safe side, set aside a good 2 weeks.