My daughter LOVES her sash. Our solution is to buy her a t-shirt which we sew/iron patches onto when the sash is full. This gives her something to pin her tab onto. I'd prefer she'd select the vest, but she's adamant about the sash. It's less money if you can find a Girl Scout t-shirt for around $10.
Get the vest instead
The sash is not big enough to hold all of the badges my daughter has earned during her first year as a Junior. Not sure where she is going to put next year's badges. My advice is to go with a vest as there is lots more space to fit the badges. Also, it is more comfortable to wear (the sash tends to slip off of her shoulder)