I know bows can get really expensive, but it seems you can tweak cheaper ones to your needs. I guess it could be like guitar picks where it's a very personal thing. They can be very varied.

When my daughter got serious about violin we bought her an old one (100 years) that she still has. The bow ended up warped and so had to be replaced, but she kept the ivory frog. A friend of mine got an expensive bow when he was a kid and I think he passed it on to his daughter. I guess quality can last.