Fibula
Their is some excellent advice here to be followed, the main thing to remember is take someone with you to look and listen, possibly your teacher. You will know by playing and listening - but take your time and do not feel that you have to be rushed into a purchase if you are not 100% about it. You are paying a lot of money and you will have it a long for your enjoyment. Dont forget the importance of the bow, this is a commmon mistake. A good dealer will always allow you to take 2 or 3 home to try.

jOhn
I tried a hampster once but the rosin on the bow didn't agree with the hampster hair.