SB,

The first thing you need to do is go to a local bowshop and have the tech size you up for draw weight and length. Then compare that to the used bows you mention. If you can afford it the Diamond Razor Edge is the best value going right now for women/youth in my opinion. I shopped a lot and ended up getting one for my g/f.

Don't get too cheap on even your first bow or you won't enjoy shooting. My g/f won't put down her Edge. She is tiny 5'-0" 99# and only pulls 25# but her Edge is really fast for the weight.