The main feature that is included in girl beds is the availability of storage space. The bed that lasts through the teen age years can be filled with accessory spaces like for studying and for storing her cloths, make up items etc.
If it is possible for you to try the bedding for some time, it will be better. This way, you will know the comfort level that you will feel with it. Try to ask the seller if you can get a sampler of it so that you can bring it home.