You may not want to invest that much on her first bow. But comparing the Passion to the the Razors Edge is like comparing a Ford Fiesta to a Mercedes E Class. Nothing wrong with the Razors Edge. It is what is, a good adjustable entry level bow. As stated before, the Passion has a drawlength specific cam on it. You will not need drawlength adjustability with her. If she can pull 35# now, a Passion with 40# limbs will be all she will ever need. The Passion is the same bow as the DXT, but with a 1" shorter brace height. If she is serious about bow hunting, the Passion would be a much better choice.

My mom is 62 years old and hunts with a Passion set on 42# with a 25" draw.